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The Compost Tea Brewing Manual

When grown in healthy soil, roots extend much deeper than the height of the shoots aboveground. Work by the Hendrikus Group (www.hendrikus.com) shows that lawn grass grown in their EssentialSoil with compost tea applications has roots extending at least 4 feet deep into the soil within 3.5 months after planting lawn grass seed. Root Photo courtesy of Hendrikus Schraven of the Hendrikus Group.

 2000, 2001, 2002 Soil Foodweb Inc. All rights reserved. No part of this work may be used or reproduced in any manner whatsoever without prior written permission from the copyright holder except in the case of brief quotations embodied in critical articles or reviews. For information address Soil Foodweb Incorporated, 728 SW Wake Robin Ave, Corvallis, Oregon 97333.
First Edition Printings November 2000, February 2001 Second Edition (US and Australia) US Printings August 2001, September 2001 (2.1), October 2001, October 2001 (2.2) Third Edition (US, Australia, New Zealand, South Africa) First US Printing March 2002 Fourth Edition, March, 2003 (US and Australia) Fifth Edition, April 2005 This publication is part of the educational outreach program of the Sustainable Studies Institute (SSI). A portion of all proceeds from sales of this publication goes to support SSI’s activities. For more information about the Sustainable Studies Institute visit their website at www.sustainablestudies.org

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As you listen to the present controversy about pesticides. who currently manufactures the Earth Tea Brewer.And Why?" Rachael Carson. and without losing the rights to be called civilized.forces careless of life or deliberately destructive of it and the essential web of living relationships. Soil Foodweb Inc. information and/or thoughts to developing my understanding of compost tea. Ingham President. www. is with the reckless use of chemicals so unselective in their action that they should be more appropriately be called biocides rather than pesticides. Keep sharing your ideas! Elaine R. Remember taking samples every two hours from the Microb-Brewer for an entire week? Right-o mate! Bruce Elliott. as you know. These are large problems and there is no easy solution. the first to build a commercially viable compost tea-brewing machine. And for everyone who is making compost tea in any form. Lismore. Southern Cross University. and has communicated with me about their results. Worldwide. I recommend that you ask yourself .
Merline Olson has been a true friend for many years. the guiding light behind the Microb-Brewer. My particular concern. NSW. Leon Hussey. 1963 address to The Garden Club of America "Her speeches during the last year of her life reflect her moral conviction that 'no civilization can wage relentless war on life without destroying itself. Sustainable Studies Institute -------------------------------------------------------------------------------------------------------------------------Contributed by Leon Hussey: “This is a time when forces of a very different nature too often prevail . who is the first person to use aeration alone to extract the organisms from compost. But the problem must be faced. info@soilfoodweb." LOST WOODS . Not even the most partisan defenders can claim that their toxic effect is limited to insects or rodents or weeds or whatever the target may be.Who speaks? .Linda Lear
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.sustainablestudies.Acknowledgements
The following people contributed time. Currently is the President of SFI Australia. Sustainable Studies Institute.org Affiliate Faculty. I would like to thank them for their help: Karl Rubenberger.com President. inventor and manufacturer of the Keep It Simple brewer. Australia Board of Advisors. and who continues to be a compatriot in the world of compost tea.

Kirk Leonard and many others were important in improving our understanding of compost tea machines and how they work. and the tea will drop into anaerobic oxygen conditions. recipe. At that time. but the methods for producing not-aerated teas are lacking. Certain organisms make specific toxins which combat disease. and thus should not be confused with compost tea. Not-aerated compost teas typically do not have additional food resources added to the brew. teas are typically produced by placing specific kinds or mixes of un-decomposed plant materials in water. Carole Ann Rollins. leaving only anaerobic bacteria. and many people are having great success in improving plant production as a result. so we went on to other projects.Introduction to the Fifth Edition
We’ve come a long way since I started working on liquid extracts of compost in graduate school. and this needs to be documented in order to make the claim that this kind of product was made. The amount of food added must be limited to enough to attain maximum growth of desired organisms but not so much that oxygen concentration drops below the aerobic level. Bruce Elliot. Compost tea “works” only because of the biology in them. In the last 10 years. so the effects are predictable? Aerated compost teas contain all the species of organisms that were in the compost. Those organisms selected by the temperature. If the food web is lost. Ray Gore. plantbeneficial product is always made is paramount. but not for the full two to three week production period. then the product should not be called a compost tea. If the compost used was immature. Oxygen content is critical. When oxygen drops below a certain level. Compost is typically not even a part of the recipe. Shepard Smith. however. Management is not possible if you can’t measure that biology. Steve Diver. and much more work is needed. although typically some aerobic organisms return to activity as oxygen returns to the ferment. The likelihood that the tea will reach low oxygen levels or be anaerobic is minimal. Fermented. But other advancements in the area of notaerated and purposefully anaerobic teas have yet to be explored. Thus the compost has to be “tea-quality”.and pest-organisms. Since the set of organisms is so significantly altered from what occurs in aerobic compost. Leon Hussey. George Hahn. enough soluble foods may be released. To have consistently beneficial tea requires knowing what you are doing. The competitive set of organisms must be present to prevent pathogen growth. regardless of any negativity some might have about this industry. Machine. Balance is critical – maximize growth. Anaerobic teas require that low oxygen levels are reached. Exactly what do the teas produced by not-aerated. anaerobic or fermented methods do to plants? How can we consistently produce each kind. Anaerobic biofilms growing in the machine can result in poor quality tea. nutrient composition. and that means being able to test and determine exactly what biology is present in the tea. Soil Foodweb Inc has worked with most machine makers and helped them to be successful. The biology in an anaerobic tea is limited to basically anaerobic bacteria and yeasts. but designated specifically as anaerobic tea. The potential variance in this product is significant. Oxygen typically reaches low levels for several days to weeks. anaerobically brewed teas should not be called compost tea. Aerated compost tea can have amazing benefits for plant production. foods present. or plant. Machine cleanliness is important too. oxygen management and compost used must be documented and understood. like antibiotics. Documenting that a consistent. organisms will grow rapidly. We need to know exactly how to produce consistent and reproducible teas of each kind.
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. but so is the diversity of aerobic organisms. methods for making aerated compost teas have been determined. There are many aerobic tea machine companies in the market. The full food web of organisms is not present in fermented tea. oxygen content in the tea brew grow during the brewing process. are only made in certain conditions. but maintain aerobic conditions. These toxins. variability was too great. nutrients can be lost and disease-causing organisms may grow. The full food web may be present if oxygen levels do not drop below aerobic levels.

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Natural processes improve soil productivity. but in order to increase organism biomass and activity. ultimately leaving a field devoid of life. addition of high levels of strictly inorganic. We reserve the use of pesticides and other toxic materials to the rare situation when some unusual event occurs that harms the biology that should be present. to grasses. Instead of solving the problem. Fertilizer sales people have been heard to say that agriculture depletes soil health and results in loss of tilth. so that the compost tea needs no further pathogen reduction. Only if soil lacks the biology required to convert nutrients from plant-not-available forms to plant available forms would addition of inorganic nutrients result in improved plant growth. Tillage needs to be reduced to the minimum possible. and in the natural world. Sustainable farming is possible. Properly made compost must be used. Compost tea production is therefore.What Is Compost Tea?
The simplest definition of compost tea is: A brewed. the soil is improved and productivity increases. Plant communities shift from bare soil. Compost is the main ingredient in compost tea. in plant-available forms. other foods are added at the beginning of the brewing period. and the Soil Biology Primer. soluble. the important parameters that result in the growth of certain organisms will be better understood. The mythology of modern agriculture is that soil productivity is set. destructive agriculture. Many growers have special ingredients they add. shrubs. Clean water comes out of healthy soil. New recipes are always being tested with the goal of achieving higher microbial biomass. The nutrients added are no longer held in the soil. Pesticides and inorganic fertilizers are not needed. Only if the process remains aerobic will the complex set of organisms extracted from the compost remain in the tea. thereby “cleaning up” the nutrients from the water moving through the soil. 1985. not extractive.. This is so different from a healthy soil. As a result. Nutrients are mined out of the soil. why are the nutrients lost through gaseous emissions? This is not what happens in natural systems. These ingredients and their effects are discussed later in this book. a “cold brewing” process. Change will occur when sustainable agriculture. Different kinds of aerated and non-aerated compost tea will provide the proper biology for different situations and will be ever-more integral parts of sustainable agriculture. sustainable systems. Nature gives growers clues with respect to what is wrong. where the soil holds nutrients. to weeds. productivity has no choice but to go downhill. unless fertilizers are added back into the soil. plant-available nutrients has resulted in an enormous problem with water quality. excess amounts of inorganic nutrients have to be added. Weeds are really just an indication that the system is not healthy. S and other minerals? Or if leaching is not occurring. and once a field is put into agriculture. matching the plant to the biology in the soil solves production problems. The complex set of organisms is needed to establish all of the benefits of a healthy soil food web in soil. 1999). Disease and pests are not significant in healthy. other papers by Ingham. if year after year. better plant production. although the correct mixes of beneficial organisms need to be matched to the type of plant (see Ingham et al. We just need to learn how to read the information being given to us. P. trees and then old growth forest. allowing growth of the organisms extracted from the compost. If the proper biology is not
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. plants and nutrients. Plant growth is typically improved. Why is water coming from “conventional” agricultural fields laden with excess inorganic N. water extract of compost. As the processes involved in producing compost tea are better defined. better soil structure. plant species change with time. or on the surfaces of plants. however. if soil health is maintained. While any one plant species is limited by its genetics. potting mix. is practiced. better nutrient cycling and less disease. if the information is read properly.

organisms. we need to put back the full diversity of bacteria. the impacts are limited. land is not allowed to recover between farming events. But if toxic chemicals are applied when the organisms are actively growing. for without that set of organisms. Spores aren’t affected as much as active organisms are by toxic chemicals or tillage. such as birds. and if transportation agents. people relying on plate methods have lead others to extremely mis-informed decisions. and then grows selected beneficials to high numbers. choose the method of supplying the organisms your soil needs to become healthy (from the point of view of the plant you want to grow) once again. impacts can be detected. snakes. Depending on what you want to do. the land and the biology could recover between extractive agricultural disturbance events. Aerated Compost Tea (ACT) ACT is a water extract of compost. in the chemically impacted agricultural valleys of modern technology. and transportation costs are too high. brewed. Plate media miss 99. Direct observation methods. and inappropriate conclusions made. fungi. As a result. Foods may or may not be added. nutrient retention and nutrient cycling cannot happen or are severely restricted. Returning the organisms needed to build soil health is required. The lack of proper biology must be dealt with immediately. How do we put back what has been harmed? It’s called compost. and disease suppression and protection are practically non-existent. and farming was done on small scale areas. if the source of compost is distant. But this is an error based on the methods that have been used. How rapidly can organisms colonize from another place? Something has to carry bacteria. windblown transfer. people will be forced to use toxic chemicals to attempt to grow plants. tillage and herbicides. Proper nutrition for the plants will be lacking until the organisms that retain nutrients in their biomass are returned to the soil. which allows beneficial organisms to grow to high numbers. and most organisms are inactive. nematodes and if possible. Extractive agriculture uses tillage and addition of excessive inorganic nutrients which harm the proper biology. “Plate count” methods assess mainly spores. microarthropods that were killed by toxic chemicals. Where. and spiders. tillage and lack of foods (organic matter) in the soil need to be put back. especially of active biomass. when soil is very dry. a small amount of good compost can be extended dramatically. The classical medical way of looking at disease-causing organisms was applied to soil. then the soil is sick. how can microbes reach a distant place? Not that many organisms in soil survive a dry. are also dead. For example. But we need to know how to make compost tea that will contain the full set of organisms needed. When there was plenty of land for “slash and burn” approaches to farming. and thus less likely to survive transfer to soil or to plant surfaces. and therefore the organisms and the foods to feed them have to be added back into the system without the luxury of “downtime” to recover. Or compost tea. The precise impact depends on conditions in the soil. at more or less the same numbers. which are dormant stages of some. is there even a source of healthy soil for colonization to spread from? The necessary diversity of organisms was killed long ago. If a highly mature compost with few active organisms is used. Since compost tea extracts the full diversity. Not-Aerated Compost Tea A water extract. protozoa or nematodes from one place to another. with or without added foods. Therefore. People who don’t understand soil biology will say that bacteria are always present. Until that happens. but not all. If no additional foods are used. the organisms will not be highly active and thus not use up
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.99% or more of the actual species growing and being active in soil. The wind can’t carry what isn’t there.present. but aeration is not provided. soil structure. show that soil biology activity is significantly harmed by pesticides. inorganic fertilizers. protozoa. at high biomass and activity levels. brewed without use of heat. fungi. But in today’s world. organisms are not typically active.

The oxygen concentration will drop. depending on the extraction force applied. Compost Leachate Passive movement of water through good compost removes soluble nutrients and a few organisms. protozoa. just before application. extremely low fungal biomass.
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. and/or potassium. and many bacteria are observed. More work is needed to achieve consistent production. Diversity of food resources and nutrients will improve as more kinds of plant materials are used in the composting process. then it should be called compost. but others are added to the finished tea. soluble foods and other nutrients need to be extracted from compost during tea brewing. As the plant material is used up. Organisms and Food Resources Bacteria. such that oxygen use is greater than oxygen diffusion into the water. salts. however. Single species of bacteria can produce bio-control effects. nematodes. high numbers of anaerobic bacteria will be extracted.. but care is also needed to make sure salts (e. nitrates) are not present in the compost. except the conditions in which a single species works is quite limited. Human and animal pathogens can abound as well. of course. Additional foods are typically added in compost tea. Anaerobic Tea A brewed water-extract but foods are added (or from the compost) to result in organisms multiplying rapidly. Once manure is composted. organisms stop growing. If the manure tea is mixed or stirred. Organisms on the surface of the plant material grow on the dead plant tissues and often go anaerobic for a period of time. Compost Extract By running water at significant pressure through compost. Antibiotics used in the animal feed are soluble and so normally extracted into the water and can cause significant problems for microorganisms in the liquid extract. and can have high numbers of nematodes. as well as maximum activity of the beneficial species. Phytotoxic compounds can be present and nutrients can be lost if the leachate becomes anaerobic. fungi. the greater will be the number of beneficial species of each group of organisms.g.. chamomile. to enhance the activity of the organisms so they will glue and bind themselves to foliage. nor provide all the benefits possible from compost tea. At the very least. since anaerobic bacteria are not as good at sticking to surfaces as aerobic organisms. If no mixing or stirring is used. nettles. but can be if organisms in the compost are growing rapidly. only soluble nutrients will be extracted and the tea will typically be high in nitrates. extremely low fungal biomass. Foliar applications require maximum coverage of the leaf surfaces. Bacterial Soups As with plant tea. Plant (or Fermented) Tea Fresh plant materials (e. but neither will the organisms stick to leaf surfaces. aerobic fungi.g. and quite interesting effects have been produced. allowing oxygen to diffuse back into the tea. Soluble nutrients. Manure tea contains high numbers of ciliates. since they are not highly active. Plant teas usually do not contain all the organisms in compost tea. and if it drops below the threshold of 6 ppm. mixes of bacterial species can have specific beneficial impacts. replaced by strictly anaerobic bacteria and yeasts. marigolds.oxygen during the brewing. Leachate is not necessarily anaerobic. the organisms and soluble nutrients can be extracted from the solids. manure tea cannot provide all the benefits possible from compost tea. Anti-microbial agents can be produced. More work on production conditions is needed. some to grow the organisms in the tea brew. for example. The higher the quality of the compost. and horsetail) can be added to water to remove plant juices. protozoa and nematodes will be lost. phosphorus. enzymes and hormones can benefit plant growth. Addition of these cultures to compost tea can add functions to the tea. Manure Tea Manure is added to water. The tea will likely not become anaerobic. as high levels can “burn” plant surfaces. Usually high numbers of ciliates.

. Filamentous fungi that build soil structure and hold nutrients are lost. If there are few aerobic organisms. ASK FOR DATA so you don’t have to do this testing yourself. Nutrient cycling will therefore no longer occur. in order that the buyer can assess whether this machine performs as advertised. Aerobic bacteria that make micro-aggregates go into dormant stages in anaerobic conditions. or sometimes for days or weeks. 3. but that is the only function it provides from a food web point of view. nematodes and microarthropods die in conditions that rapidly become anaerobic. as the organisms which cause the beneficial effects desired in compost tea will not be present. for a few hours. or nutrients can be used to improve conditions for beneficial bacterial and fungal growth in compost. Anaerobic teas may do some interesting things. and that nutrients will be lost. the brewing process has to be aerobic. The testing conditions should use: 1. If excess is added. Aerobic Conditions Aerobic conditions maintain the presence and growth of beneficial organisms. The data from these tests (a minimum of three replicated tests) must be available to the buyer. To obtain the full benefits possible from compost tea. and anaerobic organisms do not stay active nor will they perform their functions in aerobic environments. In
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. different kinds of foods. Leaf surfaces are aerobic environments.Compost Quality Compost quality is critical. The balance of amount and type of foods added determines oxygen demand by the organisms growing on those foods. and the tea becomes anaerobic or low oxygen concentrations. Anaerobic teas add only anaerobic bacteria and yeasts. and 1 gal of humic acid in 100 gal of water). when conditions become anaerobic. Prolonged anaerobic conditions mean that many organisms will become inactive or die. Anaerobic tea will not replenish the full soil food web.01% fish hydrolysates and 0. Anaerobic Conditions Anaerobic teas are much less clearly defined than for aerobic tea. then the resulting brew cannot actually be compost tea. either the food resources sold by the tea machine maker. Sometimes compost tea may become anaerobic for only a few minutes. For that reason. These additives need to be checked for pathogens. for the most part. Machine Testing Tea-brewing machines must be tested to show that adequate biomass of all groups of necessary aerobic organisms were present in the final tea. Protozoa. Aerobic compost means a habitat has been maintained that allows the beneficial organisms to out-compete the less or not-beneficial organisms that grow more rapidly in reduced oxygen conditions. nor can it be a nutrient supplier. compost with documented initial biology. bacterial and fungal growth will result in oxygen consumption to a detrimental level. or even in compost tea. or a standard set of foods. and therefore soil structure will not be maintained. 2. Testing of the machine must be displayed by the tea machine maker before anyone would consider buying a machine labeled as compost tea maker.01% humic acid (1 gal of fish. Additives of organisms. Making certain that the compost has the organisms is extremely important. if the aerobic organisms are not destroyed or put-to-sleep. You need to know what amount of food to put in the machine as temperatures change through the course of the year. for a short time. such that oxygen remains in the aerobic ranges during the tea brew. aerated conditions. anaerobic teas are not called compost teas. Care needs to be taken to not add too much food resource. The organisms in the compost have been lost. or become dormant. The soluble nutrients and foods in aerobic compost help make certain the organisms will grow in the tea brewing process. If aerobic conditions are lost. but they cannot provide the benefits discussed below that are possible with aerobic compost teas. An anaerobic tea applied to an aerobic environment may provide a physical barrier. such as 0. Brief anaerobic periods may increase diversity. the aerobic organisms will be lost.

Selection for bacterial or fungal growth can be managed during the compost tea brewing process by adding appropriate foods. and conditions during compost tea production are managed to prevent pathogen growth. the longer it will take to clean the machine. nematodes and microarthropods consume bacteria and fungi. The work Soil Foodweb Inc. 2. Anaerobic tea production parameters are still largely undefined. certain programs view compost as potentially containing human pathogens. but they lack a realistic understanding of the environment in which we live. When you smell ammonia. which compete-with facultative-anaerobe-growth in all conditions in the tea brewer. and thus release nutrients at the place. understanding the conditions selecting against pathogen growth in compost tea is vital. which are mostly facultative anaerobes. 1985. If they know what should be there. because major nutrients are converted to gaseous forms in reduced oxygen. The tea sprayer does not kill the organisms in the tea 5. A maximum diversity of each of the sets of beneficial organisms is needed in soil and on plant surfaces. Cleaning is an extremely important factor that many do not consider before buying a machine. nutrients are lost through volatilization. and P are lost as gases. has been successful.anaerobic conditions. The biology that should be present in their soils and plant surfaces. This can only be a concern if the compost is not properly made. nutrient retaining. Therefore. to prevent erosion and run-off by gluing and binding soil particles together to form aggregates. alcohol is being produced. S. Elements in the USDA take the view that even with non-manure materials. vinegar. then the risk involved in pathogens in compost tea are minimal. 2. to compete with disease organisms for food. and N. conditions. time and rates that plants require. then they can determine what biology is missing from their soil. or not. What organisms are in the compost. to grow the desired plants with as little effort as possible. all compost must be properly treated (heat or worm contact). Delivery of the missing organisms. leaving us without a working knowledge of how to predict whether the tea will “work”. and who tests their tea. There can be no question that presence of beneficial organisms improves plant growth (Ingham et al. Human Pathogens A major concern is the potential for human pathogens to grow in compost tea. Make sure no anaerobic bio-films are left in the tea brewer after a tea brew. What Growers Need to Know The point of applying compost tea is to return the biology that should be present. and soil-structure building compost tea. nutrient cycling. The greater the number of “hidden-from-view” surfaces present. Growers need to know: 1. If there are no detectable pathogens in the compost. Make sure a huge diversity of aerobic bacteria and fungi are present. to build soil structure and to allow roots of plants to grow deep into soil and find water and nutrients. Maintain aerobic conditions in order to select against pathogens. Talk to someone who owns the machine. pH is dropping. Protozoa. putrid. 3. human beings could still contaminate compost starting materials. These conditions that select AGAINST human pathogen growth are: 1. rotten egg. or sour smells.
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. 3. There would be more probability of a bird infecting your sandwich while it was sitting on a picnic table than having pathogens grow in the aerobically maintained tea. has done was to define production requirements for beneficial. Beneficial bacteria and fungi are needed to immobilize nutrients. 4. Don’t trust manufacturers to tell you the truth about cleaning issues. Therefore. USDA Soil Biology Primer. along with foods. diseasesuppressive. Even then. They will relate how critical testing and cleaning actually are. No one wants to spend hours cleaning a machine. 1995 and numerous papers on the benefits of biology to plant growth since that time).

The ratios of the different groups must be managed to promote the soil conditions that select for the growth of the particular species of plant desired. to adequate. textbooks and publications. several tens of species of protozoa. This method uses simple categories of assessment. The factors that must be considered for making certain the habitat is correct for beneficial organisms are: 1. necessary to do scientific study. They are placed in broad categories. nematodes and microarthropods. quantitative assessment. not the disease organisms (see Recipe section). conditions. and some training is needed to do this yourself. Diversity is necessary. Since most beneficials require fully aerobic conditions to function. The foods used in the compost or the compost tea need to be selective for the beneficial organisms. Qualitative Assessment of Compost Tea Perhaps one of the most exciting recent developments by Soil Foodweb Inc is a way that individuals can easily and cheaply assess every batch of tea of the organisms they want to know about. The Habitat Must Select for Beneficials The habitat in compost and in compost tea needs to select for beneficial organisms and suppress disease organisms. For more information about the soil food web. because they have a function in soil. contact your closest SFI lab (all labs on the SFI homepage. based on location world-wide). There is set-up required. Enough people are starting to get “better” than excellent levels. made from properly processed compost. but are not active and do not often cause disease. Temperatures between 65 and 85 F in tea. There might be a few disease organisms present in soil and compost.com for references.soilfoodweb. Please see the SFI web site for dates and locations. and as such. to good. so a new category of outstanding will likely be added. 3. If there are no human pathogens in the compost. or at about one to two month intervals. when oxygen becomes limiting. The qualitative assay is $25 for the categorization of tea. very good and excellent. but they are not precisely quantified. check www. in low numbers and low diversity. 2. Dormant stages of many organisms survive the composting process. The full-scale. and for processes to occur. What is a disease in one system may be a beneficial organism in another system. or reduced oxygen. from bad. but it allows a general assessment of tea quality. Even “pest” species should be present. and the way to replenish that diversity is by using compost made with a wide range of plant materials. Most plant and human pathogens require reduced oxygen conditions in order to be highly competitive. are indicators that the soil food web is not healthy. With adequate extraction.Each combination of environmental conditions selects for the activity of at least several hundred species of bacteria and fungi. The proper set of organisms needs to be present for the foods to be consumed. salts within range. or moisture drops very low. nitrates and sulfur less than 3 ppm and no toxic levels of any material. such as when soil freezes. The categories are based on the presence and concentration of organisms observed in the sample. $35 for soil or compost. Pests are designed to remove stressed plants. to poor. then there will be no human pathogens in the compost tea made from that
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. And please remember that if you don’t wish to do these assays yourself. There are always organisms performing their function. These assays are typically a factor of 10 less than the quantitative assessments. compost tea will contain what was in the compost. until the conditions become so extreme that all activity shuts down. or compost tea. Classes to train to do this work are typically held whenever enough people sign up. for example. varies between $100 and $275 depending on the number of organisms groups being quantified. pathogens win in anaerobic. so an alternative is to send the samples into the lab or to an SFI advisor.

Soils in natural systems increase in nutrient concentration as succession proceeds. Even better. but this doesn’t occur in conventional agriculture. by compaction which changes oxygen content in the soil.
Shoots Roots
Plant-feeding Nematodes
C to fungus N. 3. Based on nitrogen (N) content in plant material. The problem is. only the nutrients removed through harvest must be replaced. recalcitrant carbons
BacterialFeeding Nematodes
Organic Matter
Flagellates
Higher level Predators
Simple sugars
Bacteria
Amoebae
Dead Material
(from all boxes)
Ciliates
Is Compost Tea A Fertilizer? Nutrients are removed when crops are harvested.compost. killing organisms through osmotic removal of water). In sustainable systems. fertility should increase with time. and 4. leaching and compaction result in loss of nutrients from the soil. by use of high levels of inorganic fertilizers (which are salts. This means we need to have standards for the biology in compost as well as in the compost tea. all of them. to be “added back” to the soil each cropping cycle. Because of all these losses. those nutrients will not be held in a biology-poor soil. Thus. for example. run-off. by tillage. and vegetable soils to grow plants without requiring pesticides or inorganic fertilizers. dices and crushes the organisms. and atmosphere. because erosion. 2. A Soil Foodweb Diagram demonstrates the relationships between the sets of organisms (functional groups in boxes) needed in most crop. Figure 1. resulting in nutrient pollution of surface and ground waters. Why does this happen? What changes? The organisms that should hold both soil and nutrients in place are destroyed in conventional agriculture: 1. µnutrients to plant
FungalFeeding Mites
Predatory Nematodes
Algae P-Bacteria Lichen
Mycorrhizal Fungi
FungalFeeding Nematodes
Predatory Mites
Saprophytic Fungi
Complex. only 15 grams of N per ton of plant material is
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. and holds nutrients. compost quality is critical when making compost tea. P. conventional chemical systems require 150 to 200 pounds – or more! -of N. which slices. grassland. where the biology is managed properly. by use of pesticides which kill far more than just the target organism species. resulting in conversion of organisms metabolism from aerobic to anaerobic species. These nutrients need to be replenished or “put back” into the soil.

What test tells you what the plant will take up? Neither soluble nutrient pool concentration nor
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. it is far from the only source of N in soil. and clay. however. These sciences have ignored the fact that natural systems manage to hold nutrients. nitrite or ammonium will be cycled into these soluble forms by the organism. sands and organic matter. erosion. Leaching. If the full soil food web is present. build and maintain them). in humic materials. in dead plant material) into organism biomass and then be consumed by predators which results in release of plant-available forms of the nutrient. 200 times 15. for example. soluble form by the organisms cycling system in a healthy soil. Nor nutrients in parent material. and produce higher plant yields than any agricultural system. in organic matter. or remove the “exchangeable” forms of nutrients from the surfaces of the clays. manage to produce clean water. Only the nutrients that are soluble (dissolved in water) or that can be extracted from the SURFACES of sand. then nutrients cannot be processed from not-plant-available forms into plant available forms. not the plant production system. We have all the food we need. is converted from not plant available forms (in rocks. only 4 times 15. in sand. then forms of N that are not nitrate.000 grams of N (3 kg of N) would need to be added back per acre.removed. where 200 tons of plant material may be removed per acre. The fertilizer industry has pushed to define N as only nitrate. held by the biology in organic matter and microbial. inorganic nutrient values are used. because their methods cannot extract minerals from large chunks of organic matter. They typically dry the sample and then use extracting agents to remove the soluble forms of the nutrients from the soil solution (soluble pool). and plant production will suffer.. in an orchard where perhaps 4 tons of fruit per acre is removed per acre. while bemoaning the fact that water quality suffers. inorganic nutrients into the soil. but any not-soluble form of any nutrient will eventually be converted from its non-soluble form to the plant-available. While this is based on the soluble forms of N that most vegetable and row crop plants take up through their roots. silts. Therefore. soil chemistry labs may remove the obvious organic matter as soon as the sample arrives. And not just N. Does either approach to extracting nutrients assess bacteria? Fungi? Protozoa. If the organisms that perform these cycling processes have been destroyed by agricultural “management”. silt. At these high rates. We need to learn the lessons nature puts in front of us everyday Nutrient Pools in Compost Why is it that when you send a sample into a soil chemistry lab. Plans for cleaning up nutrients using mechanical filtration systems (requiring engineers to design. silt and clay particles and organic matter are pulled from the soil. or 3. Why are some conventional orchardists putting 1000 pounds of fertilizer per acre on their orchards each year? The “worst case scenario” with respect to harvest removal of nutrients is production of silage. The engineering and chemical answer is to load more and more soluble. Phosphorus. and compaction then result in loss of the remaining nutrients from the soil. and maybe ammonium. Most people have been told that compost is not a fertilizer. The exact value obtained for any nutrient also depends on the extracting agent used. Not in the standard “fertilizer” form (nitrate). Nutrients in humus are not extracted either. the extractants used must be known. nematodes or microarthropods? No. That statement can only be made if only soluble. compost will always be reported as being low in nitrogen? First. biological forms. all the while ignoring that nature has been successfully feeding everyone since life began on this planet. Can compost tea supply those needs? The surprising answer to this question is yes. possibly nitrite. using soil-less mixes have been suggested as solutions to the water quality problem. but as organic N. it is social systems that prevent people from having food. so in order to compare one lab’s results with another’s. Some extractants pull more nutrients than others. The human system needs to be fixed. the inorganic forms of N. or 60 grams of N per acre is needed to replace that removed by harvest.

The three pools of nutrients in soil. as well as organic matter waste products. Nitrogen is not held in rocks. Universal
Total Extractable
Exchangable Biology Soluble Bacteria and Fungi Biology
Roots
Soluble nutrient concentration does not predict what the plant will take up. just grass growing in the field. water is held by the salts. Conc. clay. combustion 10% HCl. right now. Two weeks later. If the
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. Consider the following information based on extractions of nutrients from soil. no pesticides. Bacteria has decreased slightly. Water soluble nutrients concentrations (N or P.
Components of Soil Nutrient Pools
Tests used for each pool Grind. In natural soils. Where did the “extra” phosphate come from? Did the lab have a problem? “Messed up” in their assessment? Which time? Think it through. If salt content is too high. H2NO3 Melich III Bray 2 Amm. Cl / BaCl Colwell Olsen. Rock phosphate and compost were added to achieve a value of 75 ppm phosphate. No fertilizer. no tillage. on average. The original soil contained on average only 1. while the exchangeable pool uses less and less strong extractants. These bacteria immobilize that fixed N in their biomass. The plant may not be able to take up any of that if osmotic concentration is too high. making exudates. The total extractable pool is assessed using very strong extracting agents.8 ug of phosphate per gram (ppm) of soil. Bray 1 Melich I Morgan (Reams) 1 M KCl. In both cases. sand and silt particles. It does not predict what nutrients will be solubilized in the next instant. Nitric acid. Phosphate was solubilized from a plant-not-available pool. from humus and dead plant material. it is the bacteria and fungi that make enzymes and organic acids to solubilize nutrients from rocks. until the soluble where weak extracting agents are used. and fungi had increased by nearly 2-fold. and releasing soluble nutrients. Nothing was added to the field in the intervening 2 weeks. feeding bacteria and fungi in the root system. To predict what will be made available to plants requires knowledge of what plant material is present as food for the microbes (how active will the bacteria and fungi be?). organic matter.exchangeable nutrient pool concentrations will tell you what the plant will take up. Organisms solubilize many nutrients. what population of bacteria and fungi are present that can solubilize nutrients from parent material. Figure 2. what population of predators of bacteria and fungi are present and how active they are consuming bacteria and fungi. predators are required to mineralize these nutrients into inorganic forms the plants require. but N-fixing bacteria perform the same function. no seed. Plants were growing. and the plant cannot access either nutrients or water. for examples) just indicate what is dissolved in water. or S. soil from the same field was sampled using the same methods and phosphate was 200 ppm. and tie-up those nutrients in their living biomass.

then we can begin to predict the rate at which N. Compost tea will contain many. and humic materials were added in the compost tea. and nematodes in excess of 60 per gram) and high levels of total extractable nutrients (16. Examination of any of the journals in the area of soil ecology. The most productive systems on this planet are systems which do not have.000 ug of total extractable N per gram of compost.500 micrograms of N were released into the 2000 L of water.. or Biology and Fertility of Soil.
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. For example.g.000 micrograms of N per gram of compost. but a lack of the proper biology to make those nutrients available to plants. Similarly. If we want clean water. and have foods. we have to build soil and fertility with time. inorganic fertilizer applied. will reveal that this area of investigation is beginning to be understood. Applied Soil Ecology. Compost tea contains soluble nutrients extracted from the compost. therefore. about 340 ug of exchangeable N. Compost contains both excellent biomass of organisms (bacterial and fungal biomass both in excess of 300 micrograms per gram. based on assessment of the compost after tea production. approximately 45. Compost contains many years worth of any nutrient. the activity of the predators. when soil organic matter is present. One application of compost tea would supply a small but significant amount of N. from nutrients to disease protection to weed prevention. That means. The only way to reach these endpoints is to improve the life in the soil. an assessment performed by the Environmental Analysis Lab at Southern Cross University showed that the three pools (as shown in Fig 2 above) in a good compost contained about 286 micrograms of soluble N per gram dry weight of compost. of the nutrients that were in the compost.000 micrograms of P. a continuing supply of N would be provided to the plants through the nutrient cycling processes the biology provides. This strongly suggests that compost is a fertilizer. we have to get the biology back in our soils. But the biology has been destroyed. Compost quality is critical to understand. not destroy it. soluble (and thus very leachable) forms of nutrients to maintain productivity. in order that we can maximize nutrient concentrations in the tea. Understanding the role of the organisms is all important.000 individuals per gram. And even more. or P. but not all. Natural systems don’t require additions of inorganic. plus perhaps 50% of the total pool in compost. and 17. an organic fertilizer. they will perform nutrient cycling processes. Nearly all of the soluble and exchangeable pools will be extracted. or other nutrients will become available for plant use. If we want to grow and harvest crops. e. or Soil Biology and Biochemistry. Several compost tea applications could supply all the N a crop needed. compost contains plant-available (soluble) nutrients. and then protozoa. The total extractable nutrient level is in excess in most soils examined so far. nematodes and microarthropods release those nutrients from the bacteria and fungi. we can properly interpret what part of the nutrient pool is being assessed by any soil chemistry test. protozoa in excess of 50. and have not ever had. 9.organisms are present. the organisms will cycle those nutrients into plant-available forms. a single application of one ton of compost plus compost tea could supply everything a crop needed. As long as the biology remains un-compromised by toxic chemical additions. But even more. exchangeable nutrients but an even greater pool of plant-not-available nutrients that will only be made available as the bacteria and fungi in the compost solubilize those nutrients. What then is the chemistry information that we need in order to predict what will become available to plants through the course of a growing season? If we know the extractant methods used (see right hand side of Figure 3). the activity of the bacteria and fungi. in a compost tea (2000 L or 500 gal of water using 15 pounds or about 7 kg of compost). If we then know the biology in that soil or compost. The problem in agriculture has not been a lack of nutrients. and similar levels for most other nutrients).

weed seeds. and microarthropods. or human pathogens. such as beneficial nematodes. they will out-compete disease organisms. for the most part. different kinds of foods. If the bacteria and fungi have gone through their burst of growth early in the composting process. or nutrients to improve conditions for beneficial bacterial and fungal growth. The organisms in compost tea come from the compost. and numbers of predators. Good aerobic compost should contain very few plant pathogens. but typically lacks pathogens.
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. Pathogens should be inactive and not detectable in well-made compost. if made properly (Fig 3). If the microbes are still growing and using food resources. and are truly maturing the pile. but individuals reproduce based on the habitat present in the tea. Figure 3. then heat will no longer be generated and the pile will cool. Care needs to be taken to not add so much food resource that the growth of bacteria and fungi will consume oxygen to a detrimental level and allow the compost to become anaerobic. the temperature of the pile will not cool. diversity and growth or activity can be enhanced by adding organisms. Good aerobic compost should NOT contain root-feeding nematodes. If conditions are appropriate for beneficial species to grow. Of course the need to not disturb compost during the composting process must be balanced with the need for air in the compost. whether by high temperature. competition. especially in the maturation phase of composting. Check to make sure they are without pathogens. the greater the likelihood that compost will contain higher biomass of fungi. inhibition or consumption by predators. which means documentation of the biology must be given by the seller of the product.
FungalFeeding Mites* FungalFeeding Nematodes BacterialFeeding Nematodes Flagellates Amoebae Ciliates * typically not present * Higher level Predators
Plants *Algal blooms
*Plant-feeding Nematodes
Pests and pathogens killed by high temperature. how many are in compost? Compost typically contains all the important groups that are in soil. If the habitat in the tea is more conducive to the growth of disease organisms. only beneficial bacteria or fungi. Disturbance The less disturbed the compost. All of the species and many individuals of each species are extracted from the compost. inhibition
Predatory Nematodes
Predatory Mites *
Hi N (temp) Saprophytic Fungi (includes yeasts)
Woody (fungi)
Green (bacteria)
Bacteria
(includes actinomycetes)
Organisms Well-made compost will contain. the result is the same.COMPOST QUALITY IS CRITICAL
Of all the organism groups in soil (Figure 1). These “bad guys” bacteria and fungi are selected against in the composting process. Think of the bacteria or fungal boxes in the soil food web picture above as having a dotted line down the middle: Half of the species are “good guys” and help your plants grow. The Compost Foodweb. Organism biomass. protozoa. competition. Care in providing the proper conditions are critical. while the other half are “bad guys” that decompose plant tissues if growing on plant surface. disease organisms grow. or by passage through earthworm digestive systems.

Beneficial bacteria compete with disease organisms for food. Bacteria make glues that hold them strongly on leaf. on the order of 1010 to 1011 bacteria per ml. Species diversity may be as high as 25. Good compost teas have on the order of a billion bacteria per ml (108 to 109 bacteria per ml). fungi. Some of the initial testing with the Microb-Brewer was conducted to determine the strength of the vortex in the liquid that would remove by not destroy organisms. as sources of the indigenous beneficials disappear from the landscape. DNA methods for assessing species diversity of bacteria. This type of testing must be performed with other machines.Often when anaerobic conditions occur. compost and compost tea become even more critical. these numbers mean that 100 times more tea from a bucket method might be needed to achieve the same results as from one of the commercial units that make good compost tea. If the pile remains at 140 to 150 for months and months. to make certain the physical blending performed does not macerate or disintegrate some of the organisms. the organisms will be killed by impact on the surfaces of the brewer. and should be considered putrefying organic matter (POM). you can determine whether your tea includes the beneficial organisms that you need. the organisms must be able to pass through the mesh of the compost container. Since coverage of leaf or root surfaces by the tea organisms is what is important. In this way. however. Fingerprinting methods sound promising for assessing diversity. but not crush the organisms. More advances are forth-coming in this area. root or soil surfaces. protozoa. If too much force is applied. protozoa and nematodes will be the way to determine the actual number. Given this fact. Once pulled from the compost. and must survive in the tea. it is thus necessary to apply enough energy to compost to physically pull these organisms from compost particles into the tea. Bacteria. If conditions drop below aerobic levels. This is why nutrients held in their biomass don’t leach and will not be lost from soil or leaf surfaces. If there are no
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. Compost should contain a maximum diversity of many types of bacteria. the microbes in the compost will be extracted into the tea solution. protozoa and nematodes – are present in good compost and therefore will be present in compost tea. Clearly. this is a clear indication that the pile is not compost. and some will be killed or put into dormant condition. for space.000 species to as many as half a million species in a gram of compost or tea. If water movement through the compost is adequate to pull the organisms from the surfaces of the compost. many of the beneficial bacteria will not be able to grow. fungi. and do not expect any of the benefits discussed relative to good compost to occur if POM is used. most of which are beneficial to plant growth. Higher quality compost will have a more diverse microbial population. the pile “never cools”. resulting in greater diversity in the compost tea. Do not use putrefied organic matter to make compost tea. enzymes and fingerprinting can serve to determine whether 20 specific beneficial species are present or not. Currently. and nematodes. Plate count methods are not useful for assessing diversity. and for infection sites on plant surfaces. a combination of selective media. but is enough to pull the organisms from the compost.
COMPOST TEA ORGANISMS
The “Good Guys” or beneficial organisms – including bacteria. If they are lacking. fungi. Highly aerobic teas can contain even greater numbers. then you would know to add them back to your compost or compost tea.

In order to understand true diversity in any sample. Fe. what temperature the organisms grow at. These variations are not mimicked in nay way by the growth conditions used in a laboratory. between 30 and 300 per plate.
How to Measure Bacteria and Fungi
Direct Methods are the best way to assess both active and total bacterial and fungal biomass in any material. nitrogen. using selective growth media. they will become dormant in the tea. and not increase in numbers in the tea. perhaps 20 to 30 years ago. the original sample can be used. bacteria (tiny dots and rafts of dots). use many different foods. wet-loving and dry-loving bacterial species. Samples are finished within several hours of arrival in the lab so if a different dilution is needed. as there is with plate count methods It is impossible for a single set of incubation conditions to meet the growth requirements for all the different species of bacteria or fungi. The plate that has a “countable” number of colonies. plate counts were used to estimate total or active bacterial or fungal numbers in soil. However. Figure 4. one moisture. Fungi (strands). In plate counts. Ca. or tea. so no guesswork about bacterial and fungal biomass occurs with this method. etc. with good levels of foods to grow beneficial organisms. Consider that the microorganisms in soil. no one particular type of medium can grow all the different bacteria or fungi that occur in any environmental sample. There is no requirement to know what food resource is needed to grow the bacteria or fungi. incubated at each temperature. ten-fold dilutions are typically prepared and the quantifier has to “guess” which dilutions to plate on the medium chosen. and a whole range of moistures and humidity’s. each moisture. For example. etc. a plate count assessment cannot enumerate both heatloving and cold-loving bacteria species. Direct methods can assess total and active biomass of bacteria or fungi in any kind of material. No incubation step is required using direct methods. what humidity is required by the different species. P. The desired conditions in the tea are aerobic. each humidity and each oxygen concentration of interest. The actual sizes of the bacteria and fungi in the sample are measured. species requiring high N and those requiring low N. ciliate cysts (large circles) in a compost tea. one set of limited carbon. or compost. Plate Methods are best for identifying SPECIFIC species. but how many of the total bacteria
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. plate methods would have to use several thousand kinds of food resources. The organisms are viewed and counted and there is no question that what is being counted is the organism of interest. There is no “guess” required with respect to dilution. including compost or compost tea. K. grow at many.foods to feed the beneficials. When technological methods for performing direct count methods were not particularly reliable. one humidity. concentration. is counted at 1 and 2 weeks. many different temperatures. Plates are then incubated at one temperature.

Do we have to know the names of each of these bacterial species in order to have them work for us? No. but these are unusual and very special processes which occur in particular conditions in soil). and humic acids). 10-fold. Sylvia et al. phenols.20 µg total fungal biomass per ml in good compost tea. plate count methods cannot be used to assess these organisms. and build soil aggregate structure. they cannot mineralize N. Bacteria also decompose plant-toxic materials and plant residues (especially the simple. and result in nutrients being made available in the form plants require. The plant feeds bacteria and fungi so they will build soil structure. suppress their competitors. so that protozoa and nematodes will have something to eat. But of the tens of thousands of species of bacteria added in tea. or in compost.. complex proteins.10 micrograms of active fungal biomass per ml. Ca. if the organisms are not present and functioning in soil. hormones. Bacteria build the bricks that allow passageways for diffusion of oxygen into. Plate counts always underestimate the number of actual bacteria present. P. as well as making the water-holding pores in soil. and wait for the right conditions that will allow them to wake up. Wise agriculturalists will learn to stop killing beneficial organisms with toxic chemicals and let the organisms in soil do the work nature designed them to do. Why Are Bacteria Needed in Tea? Bacteria occupy most of the leaf or root surface and thus are most effective at consuming the food resources that the disease-causing organisms would otherwise consume. retain nutrients. and the fungal strands teased free into the
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. several hundred will match the growth conditions present at this moment. simple organic acids) as well as more complex fungal foods (complex amino-sugars. so they go to sleep in the soil. which means the aggregate structures that fungi form must be broken. In soil. leaves. What are the names of these bacteria? We don’t know. retain nutrients. proteins. the bricks to make the “soil house” will not occur and further development of soil structure will not happen. decompose residues. contains both simple extractable carbon sources (sugars.e. but fungi require complex molecules as their food resource. The plant feeds bacteria and fungi.present were missed? How can you possibly know which ones were active in the conditions of your soil? Microbiology texts discuss problems with plate count methods (i. Let plants select the organisms needed. Complex molecules are needed so fungi have something to grow on in the tea. Without these bacteria. the soil. so that some portion of these bacteria can function within existing environmental conditions and suppress various cultivars or races of disease-causing organisms. tannins. and 5 . bacteria have additional functions beyond consuming foods and occupying infection sites. Fungi also have to be extracted from the compost. or more? Plate count methods are therefore NOT useful for assessing species diversity. Most of the bacteria added in the tea will not be the right ones at the moment you add the tea.. The smallest “building-blocks” of soil structure are built by beneficial bacteria. etc) in their biomass (given the C:N ratio of bacteria. and carbon dioxide out of. easy to use substrates). Bacteria occupy most of the infection sites. 1000-fold. Thus. amino acids. complex carbohydrates. There should be 2 . they also retain nutrients (N. We can’t grow them on ANY culture medium. and with as great a diversity of species as possible. Fe. and build soil aggregate structure. Water-holding capacity can never be improved and soil will remain compacted. decompose residues and build soil aggregates. which should contain 150 to 200 µg of total fungal biomass per gram. Simple carbon sources are easier to extract than more complex molecules. but what is not known is by how much numbers are under-estimated . or species richness. which would otherwise be occupied by the disease-causing organisms. 1999). Until science develops ways to inexpensively identify them. Energy must be provided during tea-brewing to extract complex molecules. etc. and suppress disease. just get the critters in tea working without worrying about their names.2-fold. keeping oxygen diffusion flowing smoothly. Fungi. S. stems. Decent compost. siderophores. it is critical to have bacteria in high enough numbers. they have to be immobilizing N in their biomass – the exception is nitrifying or ammonifying bacteria which use N as electron acceptors or donators. The plant feeds those organisms that prevent diseases around its roots.

that isn’t possible. to provide enough energy to disintegrate aggregates and to break fungal strands. Fungi tend to occupy only 5 . fecal pellets provided by soil arthropods. Ca. certain fungi compete extremely well with disease-causing organisms. or fungal-dominated soils because the microbes control nutrient cycling and the FORM of the available nutrients. we can’t grow them on ANY culture medium. they have to be immobilizing N in their biomass).
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. because fungi build the hallways and passageways between aggregates that allow oxygen to diffuse into the soil. Which set of fungi will this be? What are their names? We don’t know. just get the full diversity of fungi back and let the exudates plants produce select for desired species. Typically. produce.tea solution. fungi have additional functions beyond protecting plant surfaces from non-beneficial organism growth. but we then cannot match their function to their DNA sequence. oxygen. Of the thousands of species of fungi added in tea. it is critical to have fungi in high enough biomass and with as great diversity of beneficial species for the plant as possible to be present. We can detect their presence using DNA analysis and molecular approaches. beneficial fungi are critical components to return to the soil. by competing for nutrients. Don’t kill beneficial fungi with toxic chemicals. space and occupying infection sites. so there is no food to allow the disease-causing organisms to germinate and/or grow on the leaf surface. Or fungal interactions may be more important under those specific conditions. since high nitrogen levels help disease-causing organisms grow rapidly. S. Infection sites on the leaves may need to be occupied by beneficial fungi so that disease-causing organisms cannot infect the plant. less easy to use substrates). 2. especially fungicides. there is no plate count method that can enumerate them.20% of the leaf surfaces. so that at least some species of beneficial fungi will be functioning within the existing environmental conditions. blossoms. P. It is the fungal biomass that is most rapidly destroyed by continuous plowing. Do we have to know the names of each of these fungal species in order to get them to work for us? Until methods are available to identify them and give them names. Fe. 5.fungi are the major holders of Ca. and further development of soil structure would not occur. 3. at least in soils we have tested. requiring pH levels lower than 7. root hairs. is a better choice for trees. etc. so a bacterial tea tends to reduce fungal growth and vice versa. Thus.. water. improvement of water-holding capacity by building structure in soil. and carbon dioxide to diffuse out of the soil. For example. etc) in fungal biomass (the C:N ratio of fungi means that fungi cannot possibly be mineralizing N. visible aggregate formation would not occur as often. most trees do NOT do well with nitrate. retention of micronutrients in fungal biomass . So. In soil. building soil aggregate structure. These additional functions include: 1. The foods added to tea should help these fungi. decomposition of plant-toxic materials and plant residues (especially more recalcitrant. space. etc. organic matter. the conditions in the soil will match the conditions that are best for only a limited set of fungal species to grow and perform their functions. Nitrate/nitrite tends to select for disease conditions along the roots. or too high levels of inorganic fertilizers. and supported by the metabolites produced by fungi. This is tricky. but not destroy them. Fungal biomass is typically lacking in any field that has been plowed more than 10 to 15 times. Beneficial fungi may be needed to consume the exudates that plant leaf surfaces. stems. Soil would remain compacted. but appear to be very important for competition with disease-causing organisms. and 4. Thus ammonium. Fungi and bacteria often compete with each other for food. Thus. Without fungi. etc. One reason why applying a single bacterial species to control blossom rot doesn’t work is because the environmental conditions may not favor the growth or survival of that single species. Materials high in inorganic nitrogen are not wise additions to tea. Why Are Fungi Needed in Tea? Just as with bacteria. Plants generally require either bacterial-dominated. retention of nutrients (N. The visible aggregates that are seen in soil are built by fungi by binding together the “bricks” made by bacteria.

which therefore cannot be extracted into the tea. Flagellates and amoebae do not tolerate reduced oxygen conditions well. or breakage. what is REALLY happening is that protozoa mineralize N as they consume bacteria. If the tea becomes anaerobic at any time. For short-term tea makers. if plants are present. Anaerobic conditions could have occurred in the PAST. Thus. For example. although conditions may not be anaerobic at the time of sampling. 2. since growth will not be possible during the extraction time. or compost are indicative that anaerobic conditions occurred sometime during the production cycle. Breaking apart aggregates so protozoa can be extracted from these previously protected places. without turning. For example. this means use of good compost is critical in order to extract the protozoa from the compost. Minimizing brewing time during which protozoa are subject to changes in pressure that results in cytolysis.Figure 5. after falling below 125° F (50° C) to allow the protozoa to grow and reach minimum numbers (20. and no longer be a problem. or soil. Thus flagellates and amoebae are good indicators of aerobic conditions – if their numbers are low. Three factors are important for protozoan extraction: 1.000 per gram dry weight of compost) throughout the compost pile.
Protozoa. Protozoa eat bacteria. tolerate anaerobic conditions. 3. and indeed. Supplying energy to pull the protozoa off surfaces. fungi. High ciliate numbers in tea. a 24-hour brew time is not enough time for an increase in numbers. giving a 3 to 6 times increase in numbers. on the other hand. Teas that are brewed longer can have protozoa grow in the tea. protozoa will increase in number in the tea. of individuals. anaerobic conditions or extreme mixing pressures are indicated.
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. when scientists say “bacteria mineralize N in soil”. a pile should cool at least 1 week. these groups of protozoa will be killed. Compost needs to cool to at least 125° F (50° C) before most protozoa will start to reproduce normally. Small dots in the picture are bacteria. Basidiomycete fungi (dark brown) with clamp connections growing in brown amorphous soil organism matter. but when brewing times are short. and plants. protozoa could multiply. and only the protozoa extracted directly from the compost will be present in the tea. in a three days tea brew cycle. Ciliates. there is no time for reproduction to occur. So. but not kill them. Magnification is 250 times actual. With time. releasing nutrients that stimulate the growth of bacteria. Immature compost most likely will not have a decent set of protozoa. apparently prefer to feed on anaerobic bacteria.

every morphological type and every species that occurred in compost was found in the compost tea. Care is needed to choose compost that is mature in order to have a good set of beneficial nematodes in the compost. If there is poor diversity in the compost. Mycorrhizal fungi These fungi do not grow in tea solutions.awaits further work. Both predatory and most fungal-feeding nematodes are killed if the pile is turned too often. All these nematodes should be beneficial. P. Diverse sets of bacterial species will control pathogen growth. not at the beginning of a tea brew. only poor compost would contain root-feeding nematodes. Protozoa and Nematodes Species diversity in tea is dependent on diversity in the compost. under control. Too many bacterial-feeders could reduce bacterial populations below the level needed to suppress disease. Species Composition of Bacteria. provided the correct food resources are added or present. There are four major functional groups of nematodes in soil: • Plant-feeders are the “bad guys”. Awareness of postproduction contamination is also required. so although present. the tea will not give the benefits that would result with a healthy diversity of species. etc which are then available for plant uptake. Compost that has reached high enough temperatures for long enough (131F or 55C for three full days in all parts of the pile). The heating process during composting often kills the spores. Some of the bacterial species extracted will grow in the tea solution. performed by the Soil Microbial Biomass Service (SMBS). Therefore.Nematodes. releasing N. Healthy compost has between 15. • Bacterial-feeders consume bacteria. It is unlikely. though. but if the germinated spores do not find active roots within 24 to 48 hours of germination. • Fungal-feeders consume fungi. reducing plant growth and yield. for example). which can be extracted into the tea. Dripping water through compost is not adequate for extraction. they will die. retain nutrients. spores should be added to the tea just before application to the crop. Beneficial nematodes do not start to grow in a compost pile until after temperature drops back to less than approximately 115° F (45° C). S. Therefore. Thus predators are important controls on the foodweb system. and consume root material. The food resources present in tea may cause mycorrhizal spores to germinate after a few days. or been processed completely by earthworms (surface contact. and it is important to recognize that while one group of nematodes is detrimental to plant growth. and the good guys. Good compost normally contains fifty to several hundred beneficial nematodes per gram. however. or passage through the nematode digestive system) will not contain root-feeding nematodes. and not pathogens. they will not be viable. the pile has to mature.000 species of bacteria per gram (based on DNA sequence more different than the sequence difference between human beings and chimpanzees. this is a selective step. Thus. Fungi. most nematodes in soil are beneficial for plant growth. Like protozoa. S. It is usually of some benefit to add an inoculum of mycorrhizal spores to the final tea solution when the tea is to be used for soil drench or root applications. although spores and hyphae will be extracted into the solution from the compost. nearly all the nematodes in the compost will be extracted in good tea making machines because enough energy is applied to the compost to pull these organisms out of the compost. but the DNA analysis required to establish the set of species in highly diverse compost versus the number of species in not-highly diverse compost – or compost tea . releasing N. etc which are available for plant uptake. that all the food resources for all bacterial species will be present in even the best compost tea solution. unturned. and • Predatory nematodes consume other nematodes and keep the population numbers of the bad guys. Nematodes play a number of different roles in soil. at least two to three weeks AFTER temperature has dropped below 115° F (45° C) in order for there to even be a hope that it will contain adequate nematode numbers. decompose residues. or build soil aggregates. It is important that the food resources in the tea are selected for beneficial species.000 to 25. P. In a study using plate methods. Most pathogens cannot compete well with
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.

Wash your hands and your food to remove this bacterial load. cows. coli presence is an indicator that the possibility exists. there will be a problem. total coliforms. it means some source of contamination is occurring. non-fecal conditions. or a food preparation area. coli is surviving. if you have been getting a normal set of coliforms in soil into your food. and sooner or later someone who has not washed their hands after visiting the restroom will leave a load of fecal coliforms on these objects. etc are also surviving. because if the vegetables have a high load of contamination. there’s a possibility that E. or where animals are housed. If contamination in compost is found. This then means we need to make sure that local gardening education programs such as Master Gardeners teach this information and keep up with new information over the years. to determine where breakdowns in processing are occurring. In the study performed by SMBS. selection will be against the growth of pathogenic and pest species. humans. it is time to start investigating where the contamination is coming from. coli could still be present. Fecal coliforms exist in animal digestive systems (birds. a good washing will likely take care of the problem. in the roots of plants. snakes. If E. coli. then it is possible that the true human pathogens such as Shigella. coli shows up on the selective medium. That’s why it is a good indicator of a problem. Extraction efficiency for fungi was not great using tea-making methods. All protozoan and nematode species found in the compost were found in the tea (SMBS study. Of these groups. coli presence indicates. etc). What is going wrong? Why are cleanliness procedures not taking care of the problem? Ask for the results of E. coli doesn’t survive all that well or for that long in aerobic. then so too might the true human pathogens. Pasteurella. A less stringent set of rules is required for back-yard gardeners. a much more stringent set of rules for those processes. and should be tracked down and removed. of significant concern and which can kill people? Total coliforms are found in a wide range of habitats. But listen carefully to what was just written. however. and that sooner or later. coli can be detected. the bacteria have a chance to grow while they are on the shelf. If you apply a source of questionable material anytime 120 days before you are going to eat those vegetables without washing them. and are important for proper digestion. there is little risk from these organisms. vow to wash your hands before you eat. Instead of vowing never to touch these things again. both on your hands and on the surface of the vegetable. an investigation should then occur. rabbits. by maximizing bacterial and fungal species diversity. There is therefore. 1993). since people touch these objects all the time. benches and door handles can be good reservoirs. Therefore. Fresh vegetables sold in containers are the place where problems are likely to occur. coli can survive. Fecal E. except to say that a fecal E. coli testing when you buy compost to put on your vegetables or food crops. E. If fecal E. fecal coliforms. coli test should be performed. If E. in the package. Pathogens in Tea E. So. and E. any door handle recently opened. The questions would be:
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. coli O157 have been used to indicate human health problems with water and soil. In addition.beneficial species. and only people already sick or stressed by something else will succumb to fecal coliforms. and are not of concern. skin surface. coli is just an indicator of fecal contamination. which ones are truly of no concern (you have them on your hands. But. that a problem exists. fecal E. then the true bad guys MIGHT also be present. fungal species and biomass were found in much smaller quantities in the tea than in the compost. Fecal coliforms occur wherever people are present. of some concern. etc). the fungi extracted did not grow well in tea because they were shattered and killed by mixing and agitation. Over the last century. Fecal E. when fecal E. For example. especially if your crop production system does not have adequate aerobic organisms to out-compete the coliforms. Salmonella. These bacteria are secondary invaders. Typically. BUT if fecal coliforms are present in food.

Those conditions must be met in order for the disease organism to grow to high enough numbers to cause a problem if ingested by a person. if the machinery isn’t cleaned before it is used with finished product. making sure that the compost is not contaminated is a must. coli. because that’s part of the protection system as well. Only fecal material from people or animals sick with this pathogen contains this pathogen. 2. makes enzymes that are more capable of taking nutrients away from other bacteria when the habitat is oxygen limiting. When buying compost from a commercial source. you should ask for their E. and then in particular? All human pathogens grow much better when oxygen is limiting. below 5. Maintain aerobic conditions. This is why in lab cultures. Salmonella and Shigella generally grow – inside warm bodies.5 to 6 mg oxygen per liter of liquid. coli are truly human pathogens. coli. coli O157 is on or in their food. coli will not be removed. but then the growth of the competing organisms would be limited in aerobic conditions. Only one sub-species of E. fixed and then the piles re-tested for indicator organisms. then E. but is then added back to the pile. and consume E. or any other human pathogen. The temperature best for E. coli. What are the conditions that select for human pathogen growth in general. especially if the set of organisms in the compost was not fully active and functioning. Just consider the habitat in which E. then the other bacteria can’t grow. 3. coli and aerobic conditions. In healthy soil.1. as well as to detect the pH change that occurs when E. allow lots of aerobic organisms to grow.
Are proper temperatures developing during the composting process? Ten to 14 days at 131 degree F or higher. compost or compost tea. enzymes work better than those of the human pathogens or indicators of potential pathogen growth. There should be a separate truck or loader used at the beginning of the process with the raw materials and a different loader or truck for the finished product. Competition is limited and E. compost used to make compost tea should be processed correctly and tested to make certain no contamination of the tea is occurring. there are many other organisms. and doesn’t heat properly. 4.2 mg. coli growth is also maintained in lab culture conditions. If the growth of other organisms is suppressed. Thus. high loads of E. A stain is used to select against other organisms. While most E. If E. coli can use could be one approach. which in aerobic conditions. of the right kind. coli flourishes. The people in danger from this sub-species are those with immature or stressed immune systems. Where is the contamination coming from? Quite often composting operations forget that machinery that contacts fresh manure will carry the disease organisms into the finished material. to document that they are at least monitoring the pathogen problem. Thus. coli to grow. coli needs to grow. But some don’t grow until oxygen reaches even lower levels. coli. contamination can occur. coli can grab food away from other organisms. You should probably also ask for a report on the active bacteria and active fungi.5 mg. when we test for E. Each pathogen has a particular set of conditions within which it does best. grab food away from E. where oxygen is limiting and there are sufficient food resources.
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. coli. E. coli can grow aerobically. Compost and compost tea need to have BOTH aerobic conditions AND high diversity of active organisms in order to be a habitat that does not allow disease organisms to grow. coli grows. If E. Is re-contamination of the pile occurring? If material rolls off the pile. In aerobic conditions. The medium often contains antibiotics which kill competing bacteria and fungi. or maybe 5. Perhaps not adding any of the sugars that E. death can be a result. E. the medium contains foods selective for just E. or re-contamination will occur. both because of limited oxygen and because they can’t get food. coli. take up the space E. How limiting? In general. There is some confusion about the habitat that allows E. But these lab conditions are a far cry from the real world. Not adding sugar is the incorrect choice. The “indicator” organism. coli data.
The problem needs to be found. coli contamination will be removed by proper tea aeration. but there can be animals with sub-lethal illness that can spread the pathogen if care is not taken in the processing of the compost. coli. No single condition selects against or for E.

9 1. but from a regulatory point-of-view. a measure of variation in the results. If there are high numbers of E.28 2. coli MAY be detected. a standard EPA approved method. coli and other human pathogens can be expected.56 0. coli does not long survive in aerobic habitats with lots of competitors and consumers present. In aerobic habitats. That fact should be used more extensively in organic production. coli has been killed? No. much less grow. Does the above table GUARANTEE that E.45 E. The protozoa in the brew also consumed E. E. coli numbers to less than what is allowed in irrigation water. Results are the mean of three samples. If E. Monitoring and checking the compost is necessary. depending on the growth of competing organisms. 4. coli is present in the “compost” but too much food was added in the tea and the tea drops into reduced oxygen concentration zones. coli? Composted manure high in E. Consider these points when trying to determine if compost or tea should be checked: 1. 5.38 Activity within desired range. coli will not survive. Active Bacterial Biomass (µg) 10. Clearly there are fecal E. no matter how much molasses or sugar is added. coli in the tea. Growers of fresh vegetables for market need to understand these interactions.7 0
Good totals Below only irrigation possible if water levels aerobic for E. it’s hard to find fungi where there are so few. 2.44 High variation. coli but also high in beneficial bacteria and fungi was used as the compost to brew a tea.000 0 Really high numbers of E. it may take more than 24 hours of aeration to
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. then E. coli will not survive in the tea. E. coli SD means standard deviation of the sample values. aerobic Total Fungal Biomass (µg) 0. coli in the compost.35 0.5 1.29 Highly variable. anaerobic conditions
Compost Tea (per ml of tea) SD Comments on tea
722 53. If there are low E. The variation should be less than 10% of the mean.33 0. coli is not present in the compost. coli (along with other bacteria) to drop E. most of the bacteria were growing anaerobically 18. E. if these conditions are encouraged. Presumably. most of which were anaerobic Active Fungal Biomass (µg) 0. reduction in E. coli.5 Bacterial biomass much reduced
2. because such low levels in the anaerobic manure 1. Can Brewing Tea Remove E. (May 2003 BioCycle). with high numbers of beneficial organisms out-competing and consuming the pathogens originally present.5 Low activity using FDA staining. to assure safety for their clients.446 Lots of bacteria present. The aeration and growth of both the beneficial bacteria and the beneficial fungi out-competed E. and if adequate aeration is maintained. coli (# CFU)
Material Tested Composted Manure (per gram dry material) SD Comments on manure
44. E.Table 1. coli. 3.9 Mostly aerobic bacteria Total Bacterial Biomass (µg) 13. coli was assessed using Coli-Blue medium. If E. coli left in the tea.455 2. concentration was brought to below the risk level for vegetable production. coli numbers in the compost. there will be no E.

However. the biofilm will form a habitat for E. particularly fungi. coli was not detected in the tea. then fungal pathogens can be present and grow in the compost tea. E. coli growth. coli numbers to below detectable levels. coli. Pathogens may find a perfect home in felt or fabric bags. aerobic conditions in the compost tea maker. standard EPA methods) was used to make tea in 5 gal KIS brewers. if the compost was not properly composted. Fungal Pathogens. Ascari or eggs of helminth worms can be present in compost. Worm compost Worm compost contains worm castings plus material that did not pass through the worm digestive system. If the compost used was actually putrefying organic matter. worms have to be considered to be very small livestock. and competition from beneficial organisms prevent the growth of disease-causing organisms. then these parasites should be killed as well. If the compost was treated properly to kill E. coli were detected in the compost tea. and conditions were not correct for E. Measure oxygen. 2. Open the bottle (carefully!) and smell. along with kelp. and molasses was used in the compost tea. This information should be determined by the machine manufacturer. and if the tea lacks proper aeration. coli in the compost tea. coli will grow in compost tea. Aerate compost tea sufficiently. in well-made compost tea. enzymes and diversity that are not in as high concentration in thermal compost. so if they are extracted into the tea. which is a habitat for the growth of human pathogens. then it cannot be surprising that E. Normally. Properly made compost should prevent these from being a concern. they do not increase in number. Typically the organisms inside worms add plant growth hormones. no or very low levels of E. but contacted the outside of the worms. If the worms have been mis-treated. the tea machine maker would change the compost bag so their customers would not have to even consider this problem. coli-free compost (documented with “Coli-blue” MPN medium. and must be managed correctly to obtain maximum benefit. If the tea maker is not cleaned properly.5. But when the tea brew was well-aerated. coli would be detected in the compost tea.
In another experiment. if they are not washed and cleaned properly from brew to brew. to assure that the beneficial aspects of compost tea will remain intact and not be lost to anaerobic conditions developing? The following are some ways you can assess anaerobic conditions: 1. Maintaining Aerobic Conditions in Teas How can aerobic conditions be maintained in compost tea. food resource and growth of the organisms at different temperatures and air pressure (elevation) have been studied and the information on how to alter the food resources or aeration rate is given with the tea brewer. But production of these gases may not reach a level your nose can detect unless you accumulate the smells. seal. Therefore. E. They do not survive or grow in water. and incubate overnight at ambient temperature. or use a tea maker where the amount of compost. Use your nose to detect bad smells. Tea machine makers should test their equipment for these problems and warn customers of these possible situations. If it smells
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. then E. coli will be detected until the machine is cleaned properly. Mesh sizes of greater than 30 mesh retains these eggs. In the best of all worlds. Fill half a clean plastic bottle with tea. Weed seed will not be extracted into compost tea either. and were not present in the tea brewer.
reduce E. 3. If E.1% to 5%). the fact that humic acids and complex food resources select against fungal pathogens. then there can be no E. but they are rarely small enough to escape the compost bag. This clearly refutes statements that have been made suggesting that if sugar is used. coli were not present in any starting material. these beneficial materials will be lacking from the worm compost. coli to out compete other bacteria and E. regardless of whether sugar of any kind was added. No matter how much molasses was used (from 0.

If the tea smells ok. bare soil that needs organic matter. If the food web is in good shape. coli or other pathogens no longer detectable) can occur within 3 days.
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. recovery (E.bad. Put this tea on something that will not be harmed by the toxins potentially present. Let the area recover before growing any plant in the area. an area of weeds. This typically requires 120 days if the soil is quite poor and does not have an adequate Foodweb. for example. you aren’t aerating enough. then it probably is bad. an area with known plant diseases. If the tea smells bad. then there is most likely enough aeration and not too much food in the tea recipe.

2. on-farm recycling of waste is enhanced. 11. With time and continued use. Compost and compost tea add a huge diversity of bacteria. If all these things occur. causing stomates to open sooner and for a longer time. correctly made and applied. However.
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. Compost teas. compost and compost tea of a quality designed to improve the set of organisms relative to the plant species desired. plants take up nutrients in the tea needed to allow them to resist infection more rapidly because the beneficial biology influences leaf surface gas concentrations. improve the life in the soil and on plant surfaces. plant growth can be improved. Typically. less than half of the existing active ingredients used in pesticides have been tested for their effects on soil organisms. reducing water use by up to 50% in two years in some cases. flower. Standards for compost production and for the biological components of compost relative to the requirements of the plant are given on the SFI website (www. even when applied at rates recommended by their manufacturers. 6. soil structure is improved and more oxygen reaches the root system. making or obtaining good compost is critical. landfill space requirements can be reduced. 5. then the benefits of using compost tea for foliar or root applications can include the following: 1. nutrients are retained on the leaf surface and become available to the plant with time. increasing the nutrients the plant can access. protozoa. 17.HOW TO USE COMPOST TEA
Every chemical-based pesticide.g. stem. will increase the number of individuals and the species diversity of the communities of leaf. 9. 16. and nematodes. worker exposure to potentially harmful chemicals is reduced. see Ingham. The pests and pathogens cannot reach the plant surface. disease-causing organisms have no food and cannot grow because the exudates produced by the plant are used by the beneficial species present on the plant tissues before the disease-causing organisms arrive. 15. decomposition of plant materials and toxins is increased. Reviews of these effects are in the scientific literature (e. 4. pathogens cannot infect the plant tissues because the specific infection sites on the plant surface are already occupied by beneficial organisms. 12. seed-surface and soil microorganisms.com). This is an oversight that should perhaps be dealt with by a comprehensive government testing program. improving plant nutrition and health. herbicide and fertilizer tested harms or outright kills some part of the beneficial life that exists in soil. Thus. beneficial organisms are present in the compost. chemical input and labor costs are reduced. and beneficial microorganisms in the ecosystem are no longer killed or harmed. fumigant. Potential Benefits of Compost Tea The whole set of beneficial organisms must be extracted and survive in tea. fungi. water-retention in soil is improved. Soluble foods must be extracted or added to tea so the beneficial organisms can grow. protecting plant surfaces. and disease cannot occur. 14. 1985). 10. Thus use of compost tea is indicated when the set of organisms in soil or on plant surfaces is below optimal levels for the plant life desired. preventing toxins from being produced in the soil. if the compost is well-made. not diseases or pests.. rooting depth of the plants is increased.soilfoodweb. increasing plant health. spaces on the surfaces of plant are physically occupied by beneficial organisms. 3. chemical-based pesticides. the nutritional quality of plant produce is enhanced. 13. The beneficial organisms and the soluble foods to feed them must be extracted from the compost and survive in the tea in order to obtain the full benefit of a healthy compost tea. and will select against diseasecausing or pest organisms. 8. food resources in the tea allow beneficial microorganisms to grow. herbicides and fertilizers are no longer used. 7.

Application of Compost Tea There are two different. on the affected area. with no dilution. without regard to a per acre amount. water holding. or some other factor was not optimal. relative to how much it can be diluted based on getting adequate coverage on the leaf surfaces. Other reasons for lack of the necessary organisms in the tea may be that toxic materials were leached from poor compost. another 5 gallons for the 18 to 24 foot height. The necessary organisms may not have been extracted from the compost. so no site allowing infection is left unprotected.
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. a single 25foot (8 meter) tall oak tree may require 25 gallons (250 liters) of tea to adequately cover the leaf surfaces.. d) Improve nutrient cycling. another 5 gal for the 12 to 18 foot height. apply 5 gallons of tea per ac for each 6 feet in height of the plants. Drenching the affected plant tissue and immediate surroundings. For example. Concentration of organisms in the tea is critical. although water is often used as a “carrier”. One reason coverage is important is that beneficial organisms must consume the leaf surface exudates. 1) Foliar applications: a) Apply beneficial organisms to plant aboveground surfaces. leaving no food for the disease-causing organisms so these organisms are unable to germinate or grow.e. Generally on seedlings and small plants. If disease is visible on leaf or blossoms surfaces. then it can used at 5 gal/ac (50L/HA). so careful attention to maintaining that concentration is important. For larger plants. Another reason is that all the infection sites on the leaf need to be occupied by beneficial organisms. then tea should be sprayed directly. or the compost became anaerobic and killed the aerobes during the brewing cycle. If organism numbers are greater than this. with effects on soil structure. you do not have to worry about over-application. pro-biotic approach). because as far as we are aware. If the tea is diluted. nutrient retention and disease-suppressiveness. b) Provide nutrients for roots to improve plant growth. c) Improve life in the soil in general. where the foliar disease organism may have spread. another 5 for the 6 to 12 foot height. then the tea can be used at a lower rate. more tea is required because of the greater foliar area to cover. The critical factor with respect to foliar applications is coverage of the leaf surface by the organisms in the tea.Not all of these benefits will be observed in every case of tea application. basil. or as a foliar spray. such as tomato seedlings. but not mutually exclusive. root depth. ways of applying compost tea: as a soil drench.
2)
Foliar applications These are applied typically with no dilution. perhaps because the compost did not contain the necessary organisms. Thus. Generally. or 25 gallons per acre). b) Provide nutrients as a foliar feed. inadequate coverage on leaf surfaces may occur. If tea is within the desired range indicated on the Soil Foodweb report (see following sections on beneficial organisms in tea). typically within 24 hours of observing the first evidence of a problem. or did not grow in the tea or may have been killed during removal from the compost or during the growth process. Soil applications: a) Help develop the biological barrier around roots (i. five gallons of tea to the acre (50 liters/HA) every one to two weeks through a disease infection period give excellent protection of plant surfaces.e. an acre of 25 foot tall trees would require 25 gallons of tea (5 gallons for the 0 to 6 feet height. Under-application can lead to problems if the organisms in the tea are inadequate. peppers. Most people err on the side of too generous. should be performed as rapidly as possible. so disease-causing organisms cannot find infection sites or food resources (i. and another 5 gallons for the top foot. pro-biotic approach).. etc.

As long as the leaf material is adequately covered with beneficial organisms. If the leaf is covered adequately by beneficial organisms. the answer is yes. killed by UV. Compost tea application to vineyard in Monroe. and what was called a foliar leaf disease was in fact stem rot. or if pump pressure was too high or too low. and poor extraction energy are all factors that must be recognized as resulting in poor coverage of organisms on leaf surfaces. Eugene. there may be serious problems preventing adequate organisms in the tea (tea quality) or adequate coverage on the leaves (leaf coverage). Alternatively. Oregon. organisms will be killed.Without assessment of leaf coverage at some time during the season. if pesticide residue in the sprayer killed the organisms in the tea. The disease may have been misdiagnosed. a minimum of 60 . then disease may occur through no fault of the conceptual approach! If a leak in the machine’s pump let oil into the tea. application when UV may destroy the organisms. temperatures too hot in the brewing process or too high when spraying. pine sap. not to the leaves. or pesticide drift. can help. How would you know if the organisms are still there? Have a leaf organism assay performed.
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. Oregon
Use of a biological spreader/sticker. Pesticide residues in tanks. Figure 6. consider then that something prevented adequate coverage of the leaf surface or killed the organisms before or after they were applied. too cold water either in the tea brewing or for dilution in the spray tank. chlorine in water. The plant surface must be assessed for adequate coverage in order to make certain the tea contained the required set of organisms and that these organisms cover the plant surface adequately. there can be no colonization of the plant surface by disease-causing organisms. Testing is necessary. Does this always work? Given adequate coverage of the plant’s surface. or simply molasses. but choose a material that does not cause osmotic shock or destroy organisms. The soil needs to have a healthy food web to prevent stem rot and the tea should then be applied to the stem and soil around the plant. as part of the USDA-SARE study on Compost Tea Effects on Mildew and Botrytis awarded to the Sustainable Studies Institute. then the plant surface will remain healthy and disease cannot win in the competition for the leaf surface. If disease appears after tea is used. In Recent Experimental Results section.70% coverage of the leaf surface was required. especially if the plant is not supplying adequate food resources. such as yucca. A minimum of 5% of that coverage had to be beneficial fungal biomass in order to prevent disease from establishing on leaf surfaces. Tea organisms on the leaf surface can be removed by rain or wind. Testing is needed.

Leaf samples should be sent for analysis after the first tea spray of each season. The heavier the clay. The author of this manual would request further interaction on this situation. When assessing the need for compost. will move. phosphorus (23. As long as the leaf stays adequately covered. In the field. sulfur. so the quality of the tea and coverage of the leaf is assured. and increases the likelihood that inadequate oxygen is present. Compaction of course reduces the ability of water to move through soil. and still disease takes over. and the organisms in it. and exactly what it is you want to do. and maintain stem and leaf coverage by tea organisms every week to two weeks to keep the soil and plant healthy. Organic matter usually allows the organisms added in the tea to continue growing. Generalized Approaches for Using Compost Tea How and when do you apply compost tea? It depends on the plant. Addition of compost in conjunction with compost tea needs to be considered. determine the amount of compost by considering the amount of N needed to replace the nutrients removed in the crop. then multiple applications may be needed. apply tea to the foliage as well as using a soil drench. so added benefit is obtained from a single application of tea with greater organic matter in the soil. no problems have been observed. Once plants are planted. has not been seen before). and the foods for the organisms to consume. Organic matter can open up structure in heavy clay. the soil.000 ug/g). a drench means water should just barely begin to drip from the bottom of the pots. as long as the full 5 gal of tea is applied to the 1 acre of area.. and the organisms. The foliage and soil around the plant should be drenched by this application. in strawberry fields where methyl bromide was injected before planting. The previous crop removed between 50 and 100 pounds of N per acre (residues left in the field). and figuring out how to overcome this challenge keeps us on the cutting edge. This 5 gal of tea can be added in any amount of non-chlorinated water. the more the tea stays at the surface. A few examples are given below. and micronutrients.000 ug N per gram of compost). In the greenhouse or nursery or a field where disease has been a problem. Properly made. the seasonal cycle. If the soil does not contain an adequate food web set of organisms. What allowed diseases to be able to “win” in the competition for the leaf surface and how can we prevent this from occurring again? This situation would present a challenge to our understanding of why compost tea works. and then the tea. The sandier the soil. As always. If problems are encountered. will move deeper. In situations where disease has been serious. so soil drenches of tea may not be necessary. In pots. saturate the soil surface. Be careful that the tea does not just run along the inner surface of the pot and out the bottom of the container. if disease is observed. so unusual situations can be explored and solutions found. the further down the tea. compaction and the amount of organic matter in the soil. then this is a situation that requires attention because it is unusual (i. If tea is applied and plant surface coverage has been shown to be adequate. calcium. then a tea application is immediately indicated. soil should be wetted to the depth of the plant’s root system. in order to keep beneficial organisms functioning through the year. On a per plant basis. aerobic compost contains an amazing amount of nitrogen (16. the soil should be drenched before planting. typically 1 liter (0.e.25 gallons) of tea (water can be used as a carrier if required) is applied per 100-mm (3 inch) tall seedling when planting into the field. That means 50 to 100 pounds on N must be replaced in the
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. Soil applications The soil needs to be inoculated with the right set of organisms. How far does the tea move into the soil? It depends on the soil texture. 20 liters of tea per acre (5 gallons/ac) were applied at each two week to 1-month interval to maintain soil health. A one-time application has proven adequate to prevent soil root disease if the soil contained a reasonable food web before tea application. feedback is requested. because it presents a situation that needs to be understood. An alternative is to apply good compost around the root systems of the plants. For example.

If the plant residues from harvest are not half-gone within a month. apply compost tea instead. Making sure the compost or tea brings in the proper biology is also necessary. and only 4 to 4.5 to 6 foot tall in the organic filed. Figure 7. after harvest. then the amount of tea must be increased to assure adequate fungal application. If the tea is top quality and contains more than an adequate amount of fungi. But. Asparagus grown with an autumn application of compost (1 ton/HA) and three monthly applications compost tea through the spring growing period. then less compost tea might be used. Cambridge. with tea
Few weeds. Soil chemistry should be assessed. apply enough compost to improve the soil food web to desired ranges (1 to 5 tons/ac. and any nutrient deficiencies should be dealt with by adding fish. kelp or other micronutrients into the compost or compost tea. In the first spring following conversion to sustainable growing. but not usually enough to do more than give a foliar “shot-in-the-arm”. Without adequate fungi. P. These count as sources of N.K. The yield in the organic treatment was double as compared to the conventional asparagus. then a second application of compost tea as a soil drench is indicated. Compost tea will also contribute N. The asparagus was on average 5. Aerobic compost has a C:N of 20:1 and thus 2 tons up to 4 tons of compost should be adequate to replace the N. A good rule-of-thumb is that the residues should be half-gone within a month of harvest. No weeds to speak of were present in the organic area while asparagus could barely be seen for the weeds in the conventional field.5 to 12 tons/HA). New Zealand.
Organic. but in the first year of resuscitating soil after years of methyl bromide applications. if temperature and moisture have been in reasonable ranges. it may be necessary to apply as much as 30 tons to the acre. Richard Prew. pesticide and inorganic fertilizer applied during the summer may not properly decompose. Typically. a second application of compost should be
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. much more than needed. but no more than 10 tons to the acre (too much compost in one application will compact and possibly become anaerobic). just before fall rains or snow occur. or 2. Typically 15 to 20 gal of compost tea per acre (150 to 200L/HA) is applied as a soil drench. if the compost tea lacks fungal biomass. etc. Paying attention to just nitrate or ammonium is not going to tell you what N will become available from the organic matter and the organisms also added in the compost. with compost tea Organic. K.5 feet high in the conventional field. If that many tons of good compost are not available. Without adequate fungi. taller plants. followed by an application of compost to inoculate the proper biology. plant residues may not decompose rapidly. etc. P. if you have adequate biology present. no bare ground
Potato In the fall.soil. 1 to 5 tones to the acre is reasonable. Generally 10 tons of compost is much. in soils not destroyed by severe chemical usage. removed in the crop. It might be a good idea to apply mulch or ground “compost” material.

and then again just before blossom and again just after blossom. If the conversion to sustainable is started in the spring.applied. so variation in the foods going into the compost will continue to be extremely important. rotation of crops will quite quickly no longer be necessary. Almost any nozzle will do for applying tea. to establish and start the process of building soil structure. After harvest. add VAM spores to the tea. no guarantees can be given with respect to success in the first crop cycle. Brewing and applying another tea should be considered if fungi are inadequate. as long as the nozzle opening size is larger than 400 micrometers in diameter. Organisms in the tea increase uptake of foliar nutrients. Add foliar nutrients if the plants show any signs of nutritional limitations. then increase the gallons of tea applied to make sure adequate coverage results. as-fungal-as-possible tea as a foliar application. Canada. Figure 8. or non-growing season.
Compost Tea Application Sept 7. Monitor the soil food web annually in the fall to know what kind of compost is needed to replace the organisms that may have been lost during the crop cycle. Applying compost tea with a jet nozzle at Jolly Farmer in New Brunswick. If potato seed pieces have been treated with fungicide. then the compost tea with VAM spores should be sprayed or dribbled onto the soil below where the seed pieces will be placed. This allows the roots to become colonized with beneficial organisms and VAM as the roots grow out of the seed piece and through the compost tea inoculum. the plants should be treated with 5 gal/ac (50L/HA) of good. with 100% confidence that all the improvements that the biology can supply will actually occur in the first growing season. If the fungal component is too low. Diseases that were enhanced each year in the conventional management system because of developing resistance-to-the-chemicals no longer develop. again at 15 to 20 gal/ac (150 to 200 L/HA) compost tea as a soil drench. VAM colonization should be monitored each year in the fall in order to know if VAM spores will be needed. seed pieces should be treated with a surface spray of compost tea. 2003
At the first true leaf stage. root-feeding pests and foliar insects are excluded from these systems through the addition of a healthy food web. This means the concentration of nutrients applied as inorganic fertilizers can be sharply reduced even in the first year of conversion to biological. If VAM colonization is not adequate on the root surfaces. Nutrient cycling will begin to occur again. In the spring. Since diseases. But consider that diversity is critical to maintain a healthy food web. It is just too soon to expect. begin the cycle again.
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. when the biology has not had the entire winter.

extra teas may be required.Weather patterns can be strange. If plants looked diseased. etc all are treated the same as potato: 1. In the worst cases. tea maker or weather condition. Direct drill or strip till the row crop plant into the system.4 19. then additional applications of tea may be needed. or checking the soil to determine if the biology is present. or checking leaf surfaces to determine coverage.4% in tea Row Crops / Broadacre Crops Corn. A new approach in field crop or row crop systems is to put a perennial cover crop in the system as has been tried at Washington State University. No matter what sprayer. Apply compost or tea (20 gal. and where drift from toxic areas occurs. 2. boundaries with neighbors that spray chemicals. to improve VAM colonization. Table 2. Ernest Culberson field agent. If any diseases are scouted. Check the tea for the beneficial organisms (SFI assays).9 in tea Small size (%) 23. It is a bit of mythology that ground covers always take moisture away from the over-story plant. 3. Data from Jolly Farmer 2003 Compost Tea Potato Trial. or when it is shaded by the over-story plant. or active. either as soil drenches or foliar sprays. Check With Compost tea Differences Total Yield (cwt/ac) 304 335 + 31 in tea Market Yield (cwt/ac) 233 272 +39 in tea Large size (%) 10. Monitor leaf surfaces.3 16. use a short canopy (1/2 inch tall) plant species that goes dormant when water becomes limiting. checking to determine if the organisms are growing. both of which are detrimental to building good soil life and maintaining soil structure. lettuce. Monitor VAM colonization in plants needing mycorrhizal colonization (many brassicas are not mycorrhizal). Applications of foliar compost teas (5 gal/ac for each 6 foot height of canopy) should occur at first true leaf stage. Use compost or compost tea to do the job of putting back in the biology as well as some foods. before blossom.
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. 8. Fall application of compost (1 to 5 tons. and give peace-of-mind. can always be done. 7. Monitor residue decomposition. Those studies need to be repeated by researchers with no connection to herbicide companies. tomato. checking leaf surfaces. variation in application times and methods will occur. Instead of using a tall grass or row crop species. This reduces erosion. 5. and maintain the under-story cover year-round. Monitoring the soil food web is necessary. just remember that some beneficial organisms have been harmed. apply the teas ASAP to re-occupy the leaf surfaces so the diseases cannot win. using Russet Burbank cultivar. Studies showing ground covers take away water from the crop may have been biased by the funding source.4. Apply compost tea to the seed or to the soil in the planting row. 6. The reduction in evaporation from the bare soil surface is more than enough to make up for water use by the cover crop in the summer. 9. Along roads.0 .2 + 5. except that herbicides or tillage are then needed to bring down the cover crop in the spring.ac) or compost tea (20 gal/ac as soil drench) need to be made. fungicides or insecticides may be required to deal with a plague situation. and after blossom. If used.ac soil drench) in the spring to replace anything missing in the soil. wheat. Green “manure” cover crops have often been used. and need to be replaced or helped to be resuscitated. 4. and surprises will always be part of the growing system. with VAM spores and/or humic acids if needed.
As with any system.

and remained more productive through their whole growth cycle. water use was decreased. with either a compost tea (Nature’s Solutions product). while yield was increased. Melons in Australia. Plants with the compost tea clearly were far ahead of the inorganic fertilizer. or a common inorganic fertilizer addition. and rooting depth improved.Figure 9. Shane Gishford. Australia. used compost in the soil and three applications of foliar tea applications in the growing season. Radish grown in potting soils.
Figure 10. an SFI advisor in Brisbane. Weeds.com
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. insect pests and fungal pathogens were significantly reduced.
info@nature-tech.

but otherwise maintain a good layer on the surface so the soil does not dry out. need to be good weed mats to prevent weeds from growing in the tree rows. compost should be applied at 5 to 10 tons per acre under the rows and again. football or soccer players. apply 15 to 20 gal/ac (150 – 200 L/HA) foliar compost tea application. golfers. 3. the compost should
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. Application of pesticides or high amounts (over 100 pounds/ac) of inorganic fertilizers will kill organisms in the soil.Turf Perennial grass systems are a bit different than annual systems and turf is unique in many ways. 4. Again in the spring. 2003
Aug 2004
Orchards and Vineyards In these perennial systems. an under-story cover crop is required in the tree. should be short canopy so mice cannot girdle the trees without the predatory birds seeing them. should be colonized by the same kinds of mycorrhizal fungi as the over-story tree requires. and disease will be the likely result. and 70% to 85% sand. Apply 1 to 2 ton per acre of finely sieved worm castings or worm compost in the fall (the sieved compost should be able to shift between the blades of the grass to lie on the soil surface). or by people strolling on a lawn. or 2. Apply 5 gal/ac compost tea through the summer until diseases are gone. and should easily go senescent or dormant in a dry summer period. If aeration is needed. Compaction is a never-ending issue with grass systems of any kind. Add VAM inoculum in the tea and compost material if the roots of the grasses are not mycorrhizal enough. England. or poorly covered or thatch problem areas are grown in. apply 1 to 2 tons finely sieved worm compost/castings to highly compacted areas (the greens). In the fall. with the following results. try the following: 1. During the summer. Figure 10. The under-story plants need to be fungal dominated. Add humic acids if colonization is present but inadequate. and where needed in to fairways. Turf will be walked on. whether by grazing animals. For details contact Mike Harrington. a practice that should rapidly end as turf health improves. the grass in the inter-row areas should be mowed and blown onto the row area under the trees. Apply 5 gal/ac compost tea (50L/HA) each week until frost occurs. The food web has to be healthy enough to maintain soil structure and not succumb to compaction. Instead of toxic chemicals. 5. This allows composting to continue all summer long. tees and putting surfaces. vine or berry bush row in order to prevent herbicide sprays in the area that needs to be fully fungal dominated. Rugby Club in southern England used the typical Soil Foodweb approach. and then hold off on any more applications until spring. The under-story plant should be able to let grass clippings blown on top of the plants shift between the stems and reach the soil surface.
FROM THIS TO THIS IN ONE YEAR
Sept. Laverstoke Park. apply a good compost tea (match the needs of the soil with the biology in the tea) immediately and then fill the aeration holes with a mix of 15 to 30% medium sieve compost high in woody or fungal foods.

Leaf litter should reduce by well over 50% the amount of disease that occurs in a conventional orchard. Beds or “soil-less” potting mixes should be drenched with compost tea to establish the beneficial organisms that will protect plants. While no guarantees can be made about effectiveness. apply tea again to speed the decomposition process. This spatial heterogeneity is maintained by use of bacterial and fungal foods applied correctly to the root system and drip line of each plant. This prevents diseases from being able to grow on the leaf material and overwinter. Drench flats with compost tea to make certain the beneficial organisms are established. Hydroponics should have 1 gal of compost tea added per each 50 gals of water. after applying a strongly fungal-dominated compost tea. However. place seeds rolled in compost tea and VAM spores in 100% good compost. the entire plant should be dipped into compost tea made without humic acid (the humic acids can cause spotting of the leaf surfaces). Teas should be applied as soon as first true leaf stage is reached. If a disease outbreak occurs. as a replacement for peat moss or coconut fiber. In the case of water lettuce. 2 weeks before bud break. Drench the soil with compost tea just before sales. again. For vegetables to be planted in the field. for example. apply another 1 to 5 tons of compost followed by a soil drench of compost tea. In the spring. 1 gal of compost tea should be added to 50 gal of water to prevent disease. Foliar surfaces should be treated with compost tea (5 gal per acre) each month or more often if disease requires. it may be necessary to apply the tea each day until the disease is out-competed. Beds should be made with 30% to 100% aerobic compost and drenched with 15 gal per acre (150L/HA) asfungal-as-possible compost tea immediately before planting. Landscape Trees In these systems. Greenhouse Apply aerobic woody compost at about 30 to 50% in potting mix to replace peat moss and/or coconut fiber. in order to cover all leaf litter surface. if needed. Ponds and Lagoons Aeration is the most important factor in maintaining pond or lagoon health. apply foliar compost tea to establish the beneficial organisms on all the leaf surfaces. Work by a number of Soil Foodweb Advisors has shown that the use of tea has suppressed disease. and possibly prevented disease. Management of the proper biology is maintained in this fashion. Bare root plants should be dipped in compost tea with VAM spores (see spore package for density of spores) and then planted into the beds. a great deal more work is needed before we can say for certain that compost tea can consistently and with complete assurance work to remove disease from perennial root systems. Aquatic bulbs should be immersed in compost tea for 10 to 15 minutes before planting in order to establish the beneficial organisms around the bulb and on the roots. blights and other fungal diseases have been reversed by application of compost tea. the challenge is to maintain the soil biology appropriate for the plant desired. Leaf litter should be 50% reduced in weight within one month. fungal-dominated compost added to the trench and then filled in with the soil.be able to sift between the plant stems to reach the soil surface. in many cases effects of root rots. addition of compost tea to the watering system will reduce disease out-breaks. If the leaf residues are not 50% gone within one month following leaf fall. only apply tea in a foliar fashion once a month. If possible. Compost tea should be added periodically to the water. Soil drenches should be performed before planting and when litter or residue need to be decomposed. or dilute the compost by half or three-quarters. Avoid applying foliar teas when pollination is at its peak. Apply compost tea at 15 gal per ac after all leaf fall has occurred. Roots systems in aeroponics should be misted with compost tea instead of Hoaglund’s solution. Nurseries Potting soils should contain 30 to 50% aerobic compost. Trees may need to have root trenches dug several feet deep. wilts. Plants can contribute to
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. even though a bacterial-dominated plant is within inches of a plant requiring fungal-dominance. Then. In water systems. The proper biology will compete with. For as long as no foliar disease is found. and possibly prevent the disease from establishing on roots of trees. All watering events should include some compost tea to maintain healthy root systems and maximize rooting depth.

at 1 gallon per acre foot of water. that single application of compost tea should be adequate to re-establish the needed biology. the pond will go anaerobic. At this point. or if food resources (like manure) going into the pond or lagoon increase organism growth beyond the rate at which oxygen diffusion or photosynthesis adds oxygen to the pond. not just stirring the surface waters. Thus. aeration of the lower levels of the water in the pond must occur. the foods are present. There are additional factors to be considered in making certain compost tea is disease-free and capable of giving the best benefit. sugars. and dead plant material) or increase rate of aeration. Addition of the beneficial organisms that were lost when the water went anaerobic is a must. but as the lower layers of algae die. and aeration is occurring. As long as the pond or lagoon does not become anaerobic again.aeration. Algal blooms may be adding oxygen into the water on the surface. Either reduce input of foods (manure. Stink begins. Recovery can be rapid. any aerator needs to pull water from the bottom of the pond. Just an inoculum is needed. but if a layer of algae begins to grow. often beyond the level where the photosynthesizing algae can offset the oxygen demand. oxygen uptake increases. compost tea needs to be added to the water. Thus. The basic approach to using compost tea in conjunction with compost and soil should be apparent by this point. and the dead bodies are decomposed.
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if the bubble size is extremely small. and each tea brew can be very similar. It is important to recognize that only certain microorganisms will be encouraged. Of course. It is a wise idea to buy an oxygen probe in order to make certain the tea remains in the aerobic range (above 6 ppm or 70 to 80% dissolved oxygen – versus carbon dioxide . Aeration. and Aerobic.in solution. Added Materials. A large problem in making highly beneficial teas is when microbial growth rapidly uses up a significant portion of the oxygen such that anaerobic conditions ensue. see Table 3 below). Facultative Anaerobic and Anaerobic Organisms Type of Organism Total Atmospheric Gases Percent Dissolved Dissolved Gases (mg/L) Gases Aerobic 20 – 21% oxygen 95 to 98% oxygen > 6 mg/L oxygen 1 to 6% carbon dioxide 1 to 5% carbon dioxide Facultative 15 – 16% oxygen 75 to 95% oxygen 4 to 6 mg/L oxygen Anaerobe 6 to 12% carbon dioxide 5% to 25% carbon dioxide Anaerobe 2 to 15% oxygen < 75% oxygen < 4 mg/L oxygen > 12% carbon dioxide > 25% carbon dioxide Temperature and Percent oxygen declines Oxygen and carbon Maximum concentration of air pressure and other gases increase dioxide will always oxygen at sea level.Factors Affecting Compost Tea Quality
Compost tea can be inconsistent from batch to batch. Make certain that the kind of compost. pH. The smaller the bubble size. or selected by different foods. depending on the water depth. resulting in more diffusion of oxygen into water. Table 3. the temperature. and very different organisms can grow at different times. then airflow may be restricted because it is harder to push air through a small opening. Properly controlling oxygen input into the water is critical. or 20 to 22% oxygen as total atmospheric gases. This manual gives a basis for choosing some of these materials (see The Recipes later in this manual). Aquarium bubblers typically produce rather large size bubbles and are not very efficient oxygenators of water. and materials that are toxic to plant growth are produced in the tea. Carbon Dioxide. decreases as regardless of temperature increases or air elevation. but this variability is actually relatively easy to control. then the greater the exchange surface and the more efficient the transfer of oxygen into the water. temperature and interactions with soluble compost material. If bacteria and fungi are not growing. Relationship between Oxygen. When making tea. Combine food resource with aeration. pressure or pressure decreases temperature Oxygen has to diffuse into water at the interface between air and water. but they are very inexpensive and can run all the time. freezing (elevation) as elevation increases sum to 100% is 16 mg/L. Many ingredients can be added to compost tea to enhance the growth of specific microorganisms and provide micronutrients for plants. Thus an air pump adequate for a 5-gallon machine may not be adequate for a 500-gallon machine. By bubbling air into water that interface is increased. Depth of the water is important too. the air pressure must be greater than water pressure. Oxygen is required by all aerobic organisms. tea solutions will remain well oxygenated. but a great deal more work is needed to understand why some additives work in certain conditions but not in others. etc are maintained the same. Bacteria consume the
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. Bubblers that decrease the size of individual bubbles improve the oxygen content of water more rapidly than aerators with larger size openings to produce bubbles. since in order to produce a bubble. and water pressure increases with increasing depth. test the tea periodically to make sure the set of organisms in the tea is maintained and no unexpected problems occur to harm extraction and growth of the organisms.

and eventually die. facultative anaerobes and strict anaerobes are everywhere. If the oxygen is replenished at a rate greater than what is consumed by the bacteria. The offensive odor produced (rotten egg smell. Anaerobic organisms are not detrimental in themselves. Conversely. which is dependent on the food resources added. Therefore. and Aerobactor. vinegar or sour smell. the organisms used up oxygen at a rate faster than the
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. Adjustment to changes in temperature occur as well. before growth commences again. but usually the death of a few disease-causing microorganisms is not positive enough to offset the reduction in plant growth. Anaerobic metabolites produced are volatile organic acids (valeric acid. Teas can become anaerobic if molasses or sugar is added to the solution. 11). phenols. although it may take a few hours for that adjustment to occur. depending on the purpose of the tea application. Lack of oxygen allows the growth of facultative anaerobes (which switch from aerobic to anaerobic metabolism when oxygen levels fall below 15 to 16% O2 or 5 to 6 ppm oxygen). the tea will become anaerobic. 1997) that are very detrimental to the growth of plants and beneficial bacteria. the growth of bacteria and fungi can be so rapid that air can be drawn below aerobic levels extremely rapidly. Examples of bacteria that are facultative anaerobes are E. so that the benefits from a widely diverse set of microorganisms can be realized. Only if someone decided to add hydrogen peroxide. strictly aerobic organisms will become dormant. on and in pavement and clothing. beneficial organisms. butyric acid. the tea will remain aerobic. As the organisms grew faster and activity increased rapidly. called lag time. These microorganisms are needed so that the cycling processes within nature can occur. The organisms first adjust to the liquid environment as the organisms and the soluble nutrients are ripped off the compost by mixing and aeration. which can be detrimental to beneficial microorganisms. Facultative anaerobes include some species that are highly beneficial to plants as well as some disease-causing species. sour milk or vomit smells) is an indication of anaerobic conditions. the tea can become over-charged with oxygen. dropping below 5 ppm. or 8 µg per liter. or ozone to the water would it be likely that the water could have too great an amount of oxygen. Thus. The temperature of the water should match the temperature of the soil. and the need for a short brew cycle. on the surfaces of stones. air needs to be provided at a relatively high rate to offset the use of oxygen by the aerobic. Klebsiella. protozoa and nematodes. At a certain point. or 4 to 5 ppm oxygen while strict anaerobes require low oxygen concentrations (less than 2% oxygen) to grow. Many highly beneficial microorganisms would be lost if the tea were sterile. within an hour or less of adding molasses. The goal is to keep the tea fully oxygenated and maintain aerobic conditions. there is no compost tea maker on the market that over-charges tea. both foods and oxygen were depleted. However. sterilization of tea is not the answer. humic acids or other food resources. However. fungi. Bacillus. When dealing with tea. and Acinetobactor). When aeration is too great.” microorganism growth slows as food resources are used up. see Brinton. Organism growth in a batch of compost tea follows a typical pattern (Fig. As oxygen concentration is reduced. True anaerobic bacteria cannot tolerate O2 above 7 to 8%. and aerobic organisms will begin to grow using the organic acids produced during anaerobic metabolism. Anaerobic products may kill some disease-causing microorganisms. when oxygen is consumed at a rate greater than the rate at which it is replenished. Aerobes. Examples of some of these genera of bacteria are Pseudomonas. or leaf surfaces. but their metabolic products can be extremely detrimental to plants as well as many beneficial microorganisms. coli. The tea will become aerobic again. if the tea is allowed to continue “fermenting. on plant surfaces. the aeration rate and the rate of movement of water through the compost and tea brewer. Strict aerobes require oxygen concentrations around normal atmospheric levels (18 to 22% total atmospheric gases or 8 ppm. Oxygen will begin to diffuse into the tea more rapidly than it is consumed by bacterial and fungal growth. They live in soil. see Table 3) in order to perform the functions of life.majority of the oxygen during aerobic metabolism.

As the organisms stabilize.
Compost Tea Oxygen Levels
10
Activity (ug/ml) Oxygen (ppm)
8 6 4 2 0
0 3 7 11 15 19 23 27 31 35 39 43 47 Hours
O2 Activity
Figure 11. the greater the amount of soluble material extracted from the compost and the greater the number of organisms extracted. Organisms growing in tea consume the extracted nutrients. and more nutrients that will potentially be made available for plants. their activity reaches an equilibrium for the next few days. and aeration rate. the organisms are no longer using up oxygen faster than it can be replaced. Brewing time. The critical part of the curve is the relationship between organism growth causing oxygen to dip into anaerobic ranges. immobilize them in their biomass and keep the nutrients from washing through soil or off the leaf surfaces. all these processes will be maximized. and most of the organisms capable of being pulled from the compost are off the compost. Up to the point that most of the soluble nutrients are all extracted from the compost. These teas could not suppress foliar disease on the plants they were applied to. As a result.machine was adding air into the water. protozoa and beneficial nematodes were lost as oxygen was depleted and fell below 6 micrograms oxygen per ml (or 6 mg oxygen per L). the organisms had used up the simple. Note the lag time associated with addition to cold water which must be overcome by the organisms early in the tea brew. More soluble material in the tea means more food resources to grow beneficial bacteria and fungi. the longer the time the compost remains suspended in the water or tea solution. oxygen levels in the water dropped. In these teas (Fig 11). This curve was generated based on eight tea brews using the same recipe with 1 gal molasses and 1 gal dry kelp product. easy-to-use foods in the tea and growth begins to wane.
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. and oxygen concentration in the water begins to increase. The point at which organism activity peaked (green triangle line). At that point. because the beneficial fungal were lost. If the tea is well mixed and well aerated (see Compost Tea Production Methods). The easiest way to know how long a machine takes to make tea with adequate organism numbers in it is to measure them over time. filamentous fungi.

therefore. or if brewing times are very long. temperature must have reached AT LEAST 131 to 135° F (57° C) continuously for 3 entire days throughout the entire pile (the surface of the pile is not at 135° F (57° C). and nutrients will volatilize if the compost becomes anaerobic. the “dead-air” effect of a corner results in no replenishment of well-oxygenated water. which does not contain significant numbers of active disease-organisms. the more likely weather will change and application will have to be put off. If the tea does not contain many organisms. Thus corners can result in the production of rank-smelling materials. Thus there is a balance between extraction of nutrients and growth of organisms. a well-known phenomenon in the world of biofouling. inhibited or consumed by beneficial organisms in the compost. the material does not have to reach temperature. Many individuals will be left in the compost. If worm-compost (vermicompost) is used. For example. the organisms in the tea will use up all their food and go to sleep. Any corner of less than 120 degrees angle tends to be a place where biofilms form rapidly. With longer brewing times. Ask your compost supplier to show
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. bacteria and fungi growing in the tea can use oxygen faster than oxygen diffuses into the tea. the Microb-Brewer and the Earth Tea Brewer can produce the optimal number of organisms within 20 to 24 hours when run at room temperatures (colder temperatures require longer brew times). so the outside material must be turned to inside and temperature maintained). and most notaerated brews require 2 to 3 weeks. The longer the brewing time. and then anaerobic organisms grow in the tea with the production of potentially phytotoxic materials in the tea. It is essential. Passage through the earthworm digestive system kills human pathogens and most plant pathogens. Rodale’s books on composting. no matter if the liquid is never stirred or mixed or aerated. Each tea brewer has an optimal time for extraction unique to the design of the machine. GOOD COMPOST. If compost is properly made. 2000) requires 3 days. out-competed. Therefore. giving an optimal time for tea production. The shorter the brew time.If oxygen supply is not adequate. so the compost can be re-added to the compost pile. Only by composting correctly can this be assured. but must be adequately processed by the worms. All of the species of organisms that can be detected in the compost will be extracted into the tea. is essential. so that oxygen is rapidly depleted as microbes grow. disease-causing microorganisms will be killed. If pathogenic or pest microorganisms are present in the compost. Compost Source and Quality. that only beneficial food sources be present in the material being extracted. there needs to be a balance between the time organisms immobilize nutrients extracted from the compost and the time they will begin to colonize the container walls and produce anaerobic layers. then they too will be extracted into the tea. or static compost. the tea cannot have the benefits that organisms give that have been discussed previously. The bucket method of brewing (see Ingham. This does not mean all individuals of all species will be extracted however. although more work needs to be performed to document this in a fully scientific manner. Thus. Adequate time in the worm bin must be allowed for full processing of all materials by the worms to occur. no-nutrients added tea brews may have such low numbers of organisms in a tea that bio-films never develop and the liquid never becomes anaerobic. or in the tea. depending on the exact conditions of brewing. some of the organisms colonize the surfaces of the containers and begin to develop anaerobic layers on the container walls. and the Soil Foodweb Web Site for more information on making good compost). Despite any amount of mixing in the container. The material cannot have been anaerobic for any length of time or phytotoxic compounds may be present. the less likely it is that anaerobic bio-films can develop. and have quite negative impacts on plant growth if these anaerobic decomposition products are not used by aerobic organism growth before the tea is placed on or around the plant. How do you know compost you buy is good? Data are REQUIRED. Whether using thermal. and some trough methods of production. Not-aerated. All of the soluble compounds in compost can be extracted into the tea. A huge range of beneficial food resources is made during the composting process (see Cornell’s Handbook on On-Farm Composting.

the temperature information on the batch you are buying. Ask them to show you the data on oxygen concentration (or the reverse measurement, carbon dioxide concentration) during composting. Because the heat during composting is generated by bacterial and fungal growth, that increase in temperature also reveals whether bacteria and fungi used up oxygen and if the compost became anaerobic during peak temperature times. Temperature should, however, not exceed 155° to 160° F (68° to 71° C) and the oxygen level should not drop below 12 to 15%. When temperature reaches these high ranges, oxygen is being consumed rapidly, and anaerobic conditions, with production of phytotoxic materials, is quite likely. If compost gets too hot, does not heat enough, or becomes anaerobic, the set of organisms in the compost is not desirable. If you use poor compost, the tea will not contain the desired set of organisms. A good test of compost that you can do yourself is determining smell. It should smell like soil, or mushrooms that you buy in the store. If compost went anaerobic for a significant period of time, it will smell sour, like vinegar, or sour milk, or vomit, rotten eggs (hydrogen sulfide) or urine (ammonia). Not only will the material have lost nitrogen and sulfur (and why would you pay good money for something lacking fertility?), but it also contains phytotoxic materials that can kill your plant if they encounter any plant surface. In order to maximize populations of beneficial organisms, it is important that an adequate range of food resources be extracted from compost into the tea. This can only occur if organism numbers are adequate in the compost. It is the organisms that make humic and fulvic acids. Minerals will be extracted from the compost as well, making it critical that the salt level not be too high, and that no toxic chemicals, or at least no high concentrations of toxins, be present. Extraction and Mixing. Mixing needs to be not too much and not too little. Too rapid mixing will physically destroy beneficial microorganisms in the tea. Think about yourself impacting the wall of the container going 320 km (200 miles) an hour. If the speed of the impact would kill you, it will kill the organisms in the tea. Too slow mixing means a lack of organisms pulled from the compost, allows bio-film development to be rapid, and the surface of everything will develop an anaerobic slime with resulting phytotoxic materials present in the liquid. There are two things to understand about mixing. 1. Enough energy has to be imparted to the compost to physically remove the bacteria and fungi from the surface of the compost. Bacteria can glue themselves onto the surface of any particle in compost, and it takes significant energy to remove bacteria from these surfaces. Fungi wrap around particles and the hyphae have to be broken enough to let the strands be pulled out of the compost, but not broken so much that they are shredded into tiny pieces. Thus, most extraction methods that involve blades, whirring mixing bars, or blender action can break up the hyphae, or the bacterial cells, too much and result in poor fungal and/or bacterial biomass in the tea. 2. Uniformity of the end product, the tea, is necessary. Good mixing – enough but not too much produces both effects. Most of the commercially available machines were developed around the principles of enough aeration and enough mixing to get organisms into the tea, but not shred them to death. If brown color comes from the compost, then fungal extraction is probably good. Add fungal food resources and surfaces that will allow fungi to grow in liquids. So, BEFORE placing any dark-colored materials in to the tea water at the beginning of the cycle, add the compost into the tea maker, in whatever container you have, and make certain the compost tea-maker is mixing the water well enough to pull the humic acids (brown color) from the compost. No brown color out of the compost in the holder should instantly indicate that adequate extraction is not occurring. Additional mixing of the compost in the container will be necessary. Foam. The presence of foam on the surface of tea is considered a positive sign, but just means there are free proteins, amino acids or carbohydrates present. This can occur as the result of adding fish hydrolysate, certain organic acids or carbohydrates. If worm compost was used, excessive foam suggests a few

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earthworms were in the compost and their dead bodies are providing this source of protein/carbohydrate. Excess protein or amino acids should not occur if bacteria are growing well, although dead worms may continue to release proteinaceous materials throughout the brewing cycle. Foam can be suppressed by using organic surfactants, such as yucca or vegetable oil (not olive or canola oil!). Don’t use commercial defoamers – every single one we have tested kills the organisms in the tea. Maintaining Compost Activity. If a large amount of compost is bought to make tea during the rest of the year, be aware that the organisms in the compost go to sleep, become dormant, and don’t extract from the compost easily the older compost gets. Maintain compost organism activity by adding compost tea to the compost. Even then, we have seen a compost get so “mature” that you can’t wake them up to grow at all in a 24 hour brewing cycle. Compost for foliar compost tea applications should to be SLIGHTLY IMMATURE! That means, a little bit of temperature is a good thing – about 5° - 10° above ambient is the desired range. Mesh size of the tea bag or final filtration material. The opening size in the compost container or any filters through which the tea must pass, can affect the kind of particulate material and organisms that will be present in the tea. Mesh is a measurement of the number of holes in an inch surface area, the smaller the mesh number, the larger the size of the holes. For example, an 80-mesh screen has holes with diameters of 170 micrometers (a micrometer is a millionth of a meter). A 20-mesh screen has holes with diameters of 800 micrometers. The finer the size of the openings, the more likely only soluble components will be extracted. If the openings are too large, particulate matter in the tea may clog sprayers and irrigation systems. A variety of materials can be used, as long as they are inert to microbial decomposition. For example, polycarbonates, plastic, nylon, silk and fine-weave cotton work well, but window screening, wire mesh, and burlap may also be used. Fresh burlap should be used with caution, though, as it is soaked in preservative materials which can be extracted into the tea and kill the organisms. Consider the size of the organisms desired in the tea. The largest beneficial nematodes are around 150 to 200 micrometers (10-6 meters) in length, but only 30 to 50 micrometers in diameter. Thus, a mesh that allows organisms of this size to pass, but restricts passage of larger materials, is desirable. The openings should not be smaller than this size since then a number of the beneficial organisms would not be present in the final product. Microbes in tea. A wide diversity of bacteria, fungi, protozoa and nematodes need to be present in the compost and be extracted into the tea (see previous discussion of the organisms in tea). The greater the diversity of beneficial microorganisms, the greater the likelihood that disease-causing organisms will be out-competed on leaves, stems, roots or in the soil. Nutrient retention will be higher, because all the food resources will be used and the nutrients retained and not leached from the leaf, stem, root or soil. Plant-available nutrients will be cycled at a more beneficialto-the-plant rate, and soil aggregation will improve, along with water-holding capacity, breakdown of toxic materials and decomposition rates. When the diversity of microorganisms in the compost is low, the health of plant surfaces will be limited, and one particular set of metabolic products can accumulate to the detriment of plants and other microorganisms. Thus good compost is critical to the production of good tea (see Wagner, 2000, Rodale books on composting, the Soil Foodweb website, www.soilfoodweb.com for information about the set of organisms in good compost and how to tell if they are present). Ratio of Compost to Water. The dilution of soluble materials and microorganisms extracted into the tea is important. Too little compost will result in too dilute a tea with too few nutrients or organisms. Too much compost means not everything is extracted that could be extracted. If the “spent” compost is placed back into an active compost pile, then ”wastage” isn‘t a worry. But it may be possible to overload some tea

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makers with too much compost, such that water cannot flow through the compost and extraction efficiency will be low. Because the optimal ratio of compost to water tends to be variable, experiment with the amount of compost put in your compost tea brewing machine to find the best ratio. If your machine calls for 7 pounds or kilos of compost, try 6 or maybe 8 pounds or kilos and see if the amount makes a difference. Temperature. Temperature, humidity, evaporation and other abiotic conditions influence the growth rate of microorganisms. For example, high temperatures volatilize nutrients. Evaporation concentrates salts, while low temperatures slow microorganism growth. Obviously, these conditions can have a significant influence on the quality of the tea. Again, experiment a bit to find the optimal temperatures for your particular situation. Place the tea making equipment inside a greenhouse or shed. In hot weather, cover or shade tea-making units prevent evaporation and concentration of salt. In machines where the tea goes through a pump, the growth of microorganisms elevates the water temperature, but as long as the tea is well mixed, temperatures will not exceed 100° - 110° F (38° - 43° C). If temperature in the machine exceeds 100° F (38° C), something is wrong with the pump, or too much biofilm has developed in the pipes or tubes, suggesting that the machine should be cleaned to remove restriction of the passageways in the machine. Machines mixed using aeration, where the tea does not go through the pump, are cooled by the temperature of the ambient air and rarely have an increased temperature. In these machines, it is wise to use a tank heater to raise temperature and increase microbial reproduction. Water Source. Water high in salts, heavy metals, nitrate, chlorine, sulfur, tannic acid, carbonates, or contaminated with pathogens (human, animal or plant disease-causing microorganisms) should not be used. Where present, removal of contaminants becomes a priority before using the water. Both chlorine and sulfur can be removed by aeration. Carbonates can be removed by precipitating them with additives, and then de-gassing those additives. Contact your water treatment department or send a water sample to a testing lab for analysis. Or, try some of these simple assessments: Drink a glass of bottled water (make sure it is less than 1 ppm (µg/ml) nitrate. Drink a glass of your own water. • Bitter? May be high in nitrate. • Rotten egg taste or smell? High sulfur. • Chlorine smell? High chlorine. Keep aerating, or remove chlorine with reverse osmosis or a chlorine filter. • Slippery feel to the water? High in carbonates. Use some acid to remove the carbonate and balance the pH • Earthy taste? Algae or actinomycetes (actinobacteria) present. Find a better source of water.

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i. Gives a relative idea of whether adequate bacterial diversity is present. mechanism. The following table lists the minimum levels of each organism group required in compost (per gram dry weight of compost). even if compost. Higher than the desired range of ciliate numbers indicates lack of oxygen somewhere in the material. and up to 20% for protozoa. food. There will be variability from tea-to-tea. Flagellates and amoebae are strict aerobes. inactive and notvery-active portions of the community.e. impacts on disease. fungal-feeding and predatory nematodes.10 2 . Active Fungi – The biomass of fungi performing their functions right now. with adequate concentrations of organisms must be applied to the plant surfaces. If disease is already present. In order to see these benefits. Note that for ciliates. There is little evidence that antibiotic or toxiccompound production is a major. active and total fungi.000 20 to dry weight) 50 Compost tea 10 – 150 150 -300 2 . are the same. or infection sites. amendments used. Beneficial nematodes – These are the bacterial-feeding. dormant. 6. Cover plant surfaces at least 70%. the more likely nutrient cycling will occur in all conditions. If flagellates and amoebae numbers are above the desired range. 4. the following points must occur.. it may be necessary to displace the disease through the mechanisms of competition for space.000 1. 2. one that will begin to move the soil in the direction of improving the communities of beneficial organisms and provide the benefits discussed previously (page 7). Table 4. then even greater than minimal nutrient cycling will occur. protozoa and nematodes in a good tea. The organisms require foods to begin to grow. Ciliates prefer to feed on anaerobic bacteria and thus indicate that the conditions are conducive to anaerobic bacteria growing. or even important. Total Fungi – All of the fungal biomass present. numbers should not exceed greater than 100 individuals per ml of tea. 3. including the sleeping. The organisms have to survive the application.20 1. But that variability is not excessive. The greater the diversity of these groups.Compost Tea Standards
The desired MINIMAL ranges for active as well as total bacteria.000 10. Gives an idea of the diversity Must be adequate in order to be able to prevent diseases under all conditions. and release nutrients from the prey group into plant available forms. Therefore use of the term “biopesticide” or “pesticide” is NOT appropriate for the mechanisms by which compost or compost tea has it’s major. or most important. The desired minimal ranges for different organisms in compost or compost tea. At least 5 gallons of tea should be applied per acre (50L/HA) for leaf coverage. etc. A gram is about one teaspoon Beneficial Nematodes (#) 50 – 100 2 – 10
Active Bacteria – The biomass of bacteria performing measurable aerobic metabolism Total Bacteria – All of the bacterial biomass present. or one millionth of a gram.
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. 5. inactive and dormant. or in the tea (per mL of tea before spraying).000 20 to (per ml) 50 µg means microgram.10 150 -200 10. including active.300 2 . and typically is no more than 10% for bacterial and fungi biomass. and 15 gallons per acre (150 L/HA) for a soil drench. Protozoa – All three groups cycle nutrients from bacteria into plant available forms. as this would indicate limited oxygen conditions (anaerobic) in the tea. Active Total Active Total Protozoa (#) Bacteria Bacteria Fungi Fungi (µg) (µg) (µg) (µg) F A C Compost (per gram 15 – 30 150 . They consume their prey group. Adequate amounts of tea. mixing. 1.

Tea can be diluted if the biomass of all categories will still be within desired ranges AFTER dilution is complete. If the biomass/numbers are lower than the desired range, the amount of tea sprayed will have to be increased from the 5 gallons per acre typical to achieve the desired coverage. In all the studies performed the organisms must occupy AT LEAST 70% of any plant surface. The desired ranges are 60 to 70% for bacterial coverage, and 2 to 5% fungal coverage, for a total of at least 70% coverage. Comparison of a Not-Suppressive Tea with a Suppressive Tea How do you know compost tea is doing the job? Well, which job are you interested in? If it is protection of a plant from disease, then to document protection, you need to have plants that you know are being attacked by the disease, and you need to show that the plant does not come down with the disease. Do this experiment yourself, and demonstrate whether your tea is doing the job. Protocol: 1. Plants were from a nursery where the greenhouse was infested with blight. All plants were infested, and the greenhouse was being fumigated to get rid of the problem. Plants from the greenhouse were donated to SFI. Presumably all plants remaining at the nursery succumbed to the disease. 2. Two compost teas were made. The suppressive tea was made in an EPM 100 gallon tea maker. The not-suppressive tea was made in a home-modified version of a commercially available tea machine. The EPM machine used 10 pounds of compost (mixed 50-50 thermal and worm compost), while the modified machine used 5 pounds of compost in a fabric bag. The recipe used was the same in both machines: molasses and kelp, aerated water, at ambient temperature (about 65 F air temperature at the start; water temperatures slightly lower). 3. The teas were brewed for 24 hours, and applied to the tomato plants using a hand-held spritzer. 4. All leaves were well-covered with the straight tea. 5. Tea samples were removed for SFI methods and for plate count analysis (dilution series was begun). The process of clean-up took about an hour. 6. Leaf samples were removed from the plants (leaves were dry), stained and examined using SFI methods. 7. Tea was assessed using SFI methods (1:10 and 1:100 dilutions used), and plates were spread for plate count assessment (1:10, 1:100, 1:1000, 1:10,000 and 1:1,000,000 dilutions spread plated as needed) . Results: The following table shows the results from this study. It is clear which tea was able to protect the plant and which tea was not able to protect the plant, based on the fact that all plants died in the nonsuppressive tea trial, and all the plants lived in the suppressive tea trial. There were five plants in each treatment, and several hundred plants in the control (the plants in the greenhouse succumbing to disease when the tomato plants were given to SFI for this trial). The plate count data are shown as they would be reported from a standard plate count lab. These are the Colony Forming Units, or Most Probable Number of individual bacterial cells that can grow on these specific media, under the specific incubation conditions in the lab. The problem with Pseudomonas counts is that you cannot tell whether these are disease-causing Pseudomonas species, or beneficial species. The not-suppressive tea had higher counts of bacteria that can grow on King’s B medium, but does that mean more or less suppressive species? You cannot tell from this assay. The Cellulase-producing bacteria and fungi were higher in the suppressive tea, but not by a significant amount. In the BBC “Species Richness Diversity” Index, this difference in CFU would not result in a different index reading. So, is it significant? There is no way to tell. The number of spore-forming bacteria and fungi were higher in the not-suppressive tea, but again, were these beneficial species, or were these the disease-causing species? Just because a number is higher, and would perhaps get a higher “index value” from a BBC Lab assessment does not mean anything beneficial. A higher number of disease organisms is not a beneficial thing. The comparison of aerobic to “anaerobic” bacteria was not performed, because this is a truly meaningless

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test. Many, if not most, of the bacteria that grow on the aerobic plate are in fact facultative anaerobes. That means, they will grow on the “anaerobic” plate was well as the aerobic. So, what does it mean that some grow on both plates? Which are the strictly aerobic species, and which are the disease-causing switchers? The “aerobic/anaerobic ratio” calculated from these plate methods cannot give that information. It is a meaningless ratio unless there are data showing that plants die when the ratio is at some level, and what plants are benefited at some other ratio. Once that information is made available, then perhaps that ratio could be useful. The aerobic/anaerobic ratio has no data to back up what it means. Table 5. How to tell that tea will be suppressive. Comparison of results from plate assessments and direct assessments when tea was not able to suppress disease, compared to when tea was able to suppress disease. Tea Lacking Suppressiveness Tea Capable of Suppressing Disease Plate Methods (MPN or CFU per ml) TSA (Aerobic Bacteria) King’s B (Pseudomonads) Cellulose (Cellulase producers) Spore-Formers (Bacillus sp)

All plants lived and produced tomatoes Numbers in parentheses are Standard Deviations of three readings taken for all the lab methods. These values indicate variation levels in the measurements taken. It is clear from the direct microscopic methods which tea will be able to perform the job. Adequate fungi must be present to deal with blight. Without adequate fungi and bacteria covering the leaf surface, there will be no disease suppression. Both the assessment of the tea itself, and the leaf surface once the tea was sprayed out were predictive of whether the tea was going to be able to deal with the disease beginning to grow on the leaf surfaces. It is easiest at this time to use the direct assessment of the tea solution. Once we have the equipment to assess the leaf surface IN THE FIELD, this will become the more useful measure, most likely. Will all fungi adequately suppress disease? There is probably some specificity of fungal species which are better at occupying the spaces on leaf surfaces, or using up the foods that the disease fungi need. Do we know if those fungi were present in this tea? No, we don’t. That we had adequate fungi and bacteria present are clear. But, in the next tea made, will adequate species diversity, the right species of suppressive organisms be present? Most likely they will. But until we have methods that can measure that information, we are left to try to maximize the beneficial species in compost, and in tea, and let the plant do some of the work by putting out the foods that will feed the right fungi and bacteria to take care of the problems on the leaf surfaces.

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Brewing Methods and Machines
Each kind of compost tea machine extracts, aerates and mixes tea differently than other machines. Yet, when the machines do a good job, the results can be quite similar. As long as the factors involved in making good tea are paid attention to, extraction, survival and growth of the organisms will be maximized. Evaluation Criteria Therefore, each machine needs to be evaluated based on the following factors: 1. Aerobic? Ability to maintain aerobic conditions (above 6 mg oxygen per L). This level is based on effects on plants and leaf material. Burning, browning, lack of foliar pathogen control, lack of nutrient color improvement all indicate anaerobic toxins produced. Quite often this is also related to compaction of the compost in the container, and too many nutrients added as amendments. Extraction of organisms from the compost? Did the machine extract the ALL the different kinds of organisms? Some machines do not extract the fungi, protozoa and nematodes. Only by obtaining data about these other organisms can their presence be determined. Extraction of soluble nutrients from the compost? Did the machine extract soluble nutrients from the compost? Or are the nutrients only from added materials? Then why make compost tea? Compost compaction? If mixing and aeration are not adequate, the compost will compact, most likely go anaerobic if there are organisms growing in the tea. The tea will lose the beneficial fungi, because these beneficials require aerobic conditions in order to survive. Teas can go anaerobic because oxygen is used up by bacteria and fungi growing in the tea and in the compost. Especially if the compost does not have aerated water moving through it, the compost will go anaerobic and anaerobic products from anaerobic bacterial growth will disperse into the tea, killing beneficial aerobic organisms. Amendments? Were adequate amounts of food added to grow beneficial organisms? Or too much food, causing the bacteria and fungi to grow rapidly, and outstrip the capacity of the aerating unit to keep up with their oxygen demand? Or food supply too low, resulting in extracted organisms, but no growing organisms? The machine manufacturer should test their machine, and tell their clients the correct nutrient concentrations to balance the growth of the organisms with the aeration rate. Please be aware that higher temperatures mean less nutrient amendments can be added because the organism grow faster. In addition, water that that is higher in temperature can hold less oxygen. As elevation increases, less oxygen is present in the atmosphere, and so less rapid growth can be allowed before the water goes anaerobic. Please see the USGS website for a table of these values. Ease of Cleaning? Cleaning is serious business. In all production systems, a biological film of microorganisms, called a biofilm and sometimes much thicker than a film (up to an inch or more in thickness in some systems), develops on surfaces. With time, the deepest layer of the film becomes anaerobic, resulting in production of strong organic acids that can kill organisms in the tea, kill plant tissue if applied to them, and can etch the tea-maker’s surfaces. If the surface is metal, the metal will be solubilized and end up in the tea solution. For this reason, a metal container is not recommended. If brew time is short, and the unit is cleaned to remove the biofilm between brews, there will be little problem. Wood or plastic containers are preferable because they can be easily cleaned.

2. 3. 4.

5.

6.

Cleaning the tea maker is SERIOUS. If biofilms aren’t cleaned off, tea may contain pathogens and other toxic materials that can harm plants. A bio-film doesn’t necessarily mean things are terrible, but they always occur when a problem has been seen. Early Methods of Compost Tea Production. Bucket Method. Bucket methods date back to early Roman, Greek and Egyptian times (Brehaut, 1933, Cato’s De Agricultura, Varro’s Rerum Rusticarum Libri Tres). Many versions of’ “compost in a bucket” are still used today. Typically, the compost is either free in the water (which means that the non-soluble chunks have to be strained out of the tea if you want to put it through a delivery system) or suspended in a sack or bag, along with other non-soluble ingredients.

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and quite often. anaerobic conditions develop or toxic materials are extracted into the tea. oxygen diffuses into the drops. But these teas are not likely still anaerobic when applied on plant material. Trough Method. and that benefit to plant growth can be significant. If the tea is used in a backpack sprayer. an occasional brisk stir helps the quality of the tea. because not enough energy is applied to the compost to physically remove the organisms from the compost. Aerators are often used to supplement air diffusion into the water. sugars. Add molasses or another food source for bacteria or fungi. concentrating salts in the tea. leaving the insoluble solids to be returned to the compost pile. but in tea that is not aerated. tape (waterproof tape. The trough can range in size from 5 to 500-gallons (20 to 2000 L). Ashville. NC. After brewing. The soluble portion of the tea can be decanted from the top. but biofilm formation on surfaces is not usually that great. However. Longer is ok. Brew for 2 to 3 days. This is not useful at a commercial level however. or growth of bacteria and fungi will use oxygen in the air faster than the aquarium pump can replace it. as desired. for example an old horse trough . however. Water is pumped from the tank. Bucket-Bubbler Method (based on work by Pat Battle at Highland Inn. with enough space for bubbling (DO NOT compact the compost or extraction will be poor and the tea may also go anaerobic). Stir periodically with a stick. if the brewing has gone on long enough.
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. this typically causes the tea to become anaerobic. did not jump-start nutrient retention. it may be necessary to strain the tea through cheesecloth. Brew times need to be several weeks long. Immature compost can be a problem. Still. humic acids. or some other food resource for the bacteria or fungi is added. minimum. and allowed to drip through the compost. These are typically the production methods from which we hear reports about “the tea killed our plants”. and can result in highly anaerobic teas. On the bottom of a 3 to 5 gallon (15 to 20 L) bucket. but realize that the amount needs to be kept minimal. into the tank. UV light kills many of the organisms in the water droplets if the unit is outside. A more modern version of “compost in a bucket” is one used by many homeowners and backyard gardeners because small quantities can be made inexpensively. The aerator provides a continuous flow of air and creates enough turbulence to provide mixing. within an inch of the top for stirring to occur. Fill the bucket half-full with water and bubble air through the water for 10 to 20 minutes before adding the compost. or a fine mesh tea sieve to prevent plugging the sprayer nozzles. diversity of bacteria and fungi is typically quite limited in these teas. In this version. Evaporation can be a serious problem. which mixes the solution as well as adding a small amount of air. or nutrient cycling. The teas produced were not within the desired ranges. Because the water is sprayed onto the compost. Bio-films typically form on trough surfaces. The following table shows results from replicated trials with the Bubbler and the Trough methods. in most cases. because poor compost. or build soil structure or consume toxic compounds. As the water drops fly through the air before impacting the compost. sprayed over the compost. Oct/Nov 2000). especially in the corners of the tank and can result in amazing smells for a portion of the brew cycle while the few bacteria that are extracted grow rapidly in the tea. by removing the organisms from the surface of the organic matter. Add compost to fill bucket to nearly the top. as in several weeks. in order to get any of the organisms extracted from the compost. Then turn the aerator off and let the brew settle for a halfhour until most of the solids are on the bottom of the bucket. Ingham in Kitchen Gardner.Fill the bucket half-full with water and stir vigorously for 10 to 20 minutes to de-gas any chlorine. please!) air stones or bubblers attached to an aquarium-type pump. Molasses or sugar can be added. It would be better to use round-bottom containers. because there isn’t much food for the organisms in mature compost and the bacteria won’t grow rapidly enough to use up oxygen more rapidly than it can diffuse into the water. and summarized by E. like water through coffee grounds. A few organisms will grow.thus the name of the method. Add the compost until the container is full. the solution is strained and applied to the crop (see Application Methods on page 18). compost is suspended on a wire tray over a large tank of water. Nutrients are of course extracted from the compost. plants were not protected from disease organisms. but typically not enough to maintain enough oxygen in the tea if molasses. The brewing period generally has to be quite lengthy.

Table 7. starting materials (1% molasses. For this reason. Microb-Brewer Tea Results. the pipes that used to occur on the bottom of the Microb-Brewer were replaced with clear plastic tubing. Composts chosen for use were widely variable. starting materials (1% molasses. 2002 In the tea grant sponsored by the Sustainable Studies Institute. Comparison of Microbial Numbers Using Bucket Bubblers and Trough Brewing Methods. C 100. 1% kelp). not just the Microbrewers. F. 1000. so the level of resolution assessed means only one kind of variation was assessed. Cleaning ANY tea-making machine. Microbial populations in tea produced by different methods. As an example of an unforeseen problem. water. Same quality compost. so users can see when a bio-film is forming. Protozoa = F stands for flagellate numbers. A.
Production Method Bubbler Trough Desired Range Brew Time 3 days 3 weeks NA Temperature Active Total above ambient Bacteria Bacteria 1 – 2° F No increase NA None detected None detected 1 µg 1 µg Active Fungi None detected Total Fungi 10 µg Protozoa (see below) F. regardless of conditions. R for root-feeders. was clearly outstanding.398 45 11 B 3 F 1P 2000 96 536 12. food resources and so
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. using their own choice of composts.000 50 2 – 10 B. with nutrient starters sold by the companies or prepared by the grower. and yet the teas produced were quite similar. temperature.5 1524 2. without any biofilm formation in the pipes.Table 6. 0. compare the result from the Microb-Brewer year 2000 test with the Microb-Brewer year 1999 test. water source.679 145 43 B 2 F 3P Desired Range 10 . C for ciliate numbers Comparison of Different Commercial Brewers The Sustainable Studies Institute Tea Grant. 20 hour brew time in both years. 0 0. Microb-Brewer Results. A for amoebae numbers. The solution is easy: Use a long-handled brush to clean the bio-film out of the pipes at the end of the run. and P for predatory nematodes (beneficials). R for root-feeders. But good tea machines resulted in good organism numbers. resulting in poorer organism numbers in the tea because of anaerobic conditions that develop. P Nematodes = B stands for bacterial-feeder numbers. and cleaning conditions were widely variable. is a VERY important step in equipment maintenance. growers made tea using the machines they bought. A for amoebae numbers. 1998 to 2000. This is opposite claims by some tea machine makers that because compost.250 1. In the year 2000 test.300 2 – 10 2.20 µg
10 – 150 150 – 300 µg µg
Protozoa = F stands for flagellate numbers. The Microb-Brewer 1999 tea. Active Total Active Total Protozoa Bacteria Bacteria Fungi Fungi (#/ml) Nematodes (µg/ml) (µg/ml) (µg/ml) (µg/ml) F A C (#/ml) 1999 138 1235 32. 2000 1000.546 3. assessing total and active bacteria and total and active fungi does not take into account species diversity per se. F for fungal-feeders. and P for predatory nematodes (beneficials). 1% kelp). F for fungal-feeders. F. Similar quality compost. 25.20 1. 1999 versus 2000. 50 Nematodes (see below) 1B 5B 2. while poor tea machines rarely produced decent organism numbers.5 21 2. Of course. and toxic materials produced by those anaerobic organisms.10 µg 2. P
None None detected detected 1 . this machine had significant bio-film formation in the pipes. C for ciliate numbers Nematodes = B stands for bacterial-feeder numbers.150 150 . brew time as indicated.000 1.10 B.

with the same amount of molasses and soluble kelp per volume of water added to each machine. consider cleaning ease. some sent in three. and quite likely a true difference in the ability of the machine to extract organisms from the compost. Results. but the only testing has been with the manufacturer. the amounts needed for each machine measured. This is excellent. But be careful – some manufacturers have been known to use compost with a higher-than-normal amount of chunky material to make it seems like the machine has good water flow. the teas were made at SFI by SFI technicians (maintained at 72 F. typically via whatever method was available to move tea from the tea-making machine into the spray tank of a sprayer. The most notable finding is that despite widely different sources of compost. the teas were made by growers. Growers were requested to make their composts from 50% thermal compost and 50% vermicompost. Results are listed by machine type and volume.forth are so different from tea brew to tea brew that the teas are so variable that consistent data cannot be obtained. Without water movement through the compost. When water cannot move through the compost. Bio-film build-up occurs. and nematodes at SFI.
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. Cleaning then becomes an important factor. this is noted. new machines have come on the market. Compost compacts in the basket. In some instances. 2. and when considering different machines. Visit trade shows where the machines are running. then there is quite likely something wrong with the machine. Put your hand in the compost in a machine to see if water is actively moving through the compost. Usually build-up within one brew cycle is not a problem. organisms cannot be extracted from the compost and organisms will be lacking in the tea. The compost was mixed well before use. and different machine designs. but in most cases. but generally what that means is the tea maker is trying to disguise an inferior machine. using non-woody compost. using de-gassed Corvallis city water). Some manufacturers have suggested that there is so much variation from tea to tea that testing is meaningless. 3. a few sent in more teas. Clearly. Check in-use machines to determine flow-through in the compost. teas were made according to the manufacturer’s directions. it is quite likely that the compost will become anaerobic during the brew cycle. the tea will always have organism numbers above the minimum levels on the desired range of the SFI test. the resulting teas were reasonably uniform with respect to achieving minimal levels of bacterial and fungal activity and biomass. or New York. If there was no discharge pump. Each sample was assessed for total and active bacteria. One to three sub-samples of tea were removed from the machine. Some machines are difficult to clean. and climate conditions. the material compacts. protozoa. except where water flow does not occur. Some growers sent in one tea. The number of samples in each assessment below are given in the table. In some cases. Some machines routinely have much higher fungal or bacterial biomass than others and there are machines that ALWAYS give higher then the minimal range on the SFI test. In several instances we have documented that the reasons some machines cannot extract organisms from the compost are: 1. and sent overnight mail to SFI Corvallis. different food additives. making water movement impossible through the compost. placed in the unit. ingredients. total and active fungi. but if the compost has decent organism levels. In the following study. Only tea machine makers trying to hide the fact that their machine cannot make consistent brews would use arguments that testing is not possible. Each machine was run for the specified time. Growers need to recognize that brew-to-brew differences based on different composts. when in fact. tea contains reasonably the same bacterial and fungal biomass and same levels of activity if decent compost and recipes are used. and the results should be available next year. Samples were sent to the lab by overnight mail in plastic water containers filled a third to a half full. and temperatures are reasonably warm. similar food resources are added. and different weather conditions are possible. The tea grant will be repeated in 2003. If the machine does not achieve the same minimum levels of organisms from tea brew to tea brew when using similar compost. using the instructions received from the tea machine manufacturer.

Is the mesh on the basket.hour aerobic brewing process. but not present. 3. Did they lack food? Did they lack a surface to grow on? No active fungi. Did something in the tea kill them? Minimal amounts of total bacteria and total fungi (extraction occurred). that bacteria may increase by 100 to 500 times the original number during a brewing cycle. Were the organisms extracted? If neither active nor total fungi or active or total bacteria are present.
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. Ciliates look like kidney beans and swim rapidly through the soil solution looking for bacteria. but no active biomass. Their life cycles are longer than the duration of a compost tea brew cycle. protozoa or fungal biomass were low in the compost. Were they killed by too much pressure going through a pump? No organisms at all present. however. there’s a good indication that extraction is the problem. If nematode. minimal biomass of total fungi. He has invested a great deal of effort in determining the best recipe of foods to grow fungi in his tea maker. If the organisms are present in the compost. that often explains low biomass or numbers in the tea. but what is seen is covered with bacteria that do not stain with the activity stain. Remember. Did the tea drop into limited oxygen or anaerobic conditions? Low active and low total fungi. or low. Ciliates need to eat at least 10. In addition. EPM has just developed a 22 gal tea machine. and so far. In the cases where we have data. is getting as good organism numbers in the tea as their other tea brewers. 2.000 bacteria per day to stay alive. For example. then the reason for the lack of those organisms needs to be determined: 1. Bruce Elliott who makes the Earth Tea Brewer machines has worked with SFI since he started building tea makers in 1999. 5. the smaller dots. it is interesting to compare the tea data with the compost from which the tea was made. while fungi may only increase by 5 to 10 times. in the tea. Fig 13. Organic matter (out of focus) in the lower left. 4. bag or compost container a problem? Neither active nor total fungi can be a result. On a daily basis then. per ciliate. Protozoa and nematodes DO NOT increase in numbers in a tea cycle. that is nearly a µg of N released in a plant available form.

or all that results is cytoplasm soup as the organism’s impact on soil particles and disintegrate. the liquid is kept aerated. irrigation systems of any kind. and a 90% reduction in activity occurred (work performed for ARDEO. After 8 hours. Fine mists result in drop sizes so small that the organisms should not be applied mid-day. up to three to five days.Application Methods
Compost tea. and the organisms have used up most of the easy-to-use food resources. Active organisms are necessary for foliar protection. drip. because UV will not be blocked. but the drop sizes should not be so small that UV light harms the organisms. Tea can also be applied to drench the soil surface. sprinkler heads. with maximum levels of oxygen in the tea. Most pivot sprayers make drop sizes large enough that tea can be applied at any time of the day (study done in the summer of 2002). but the point is to apply enough organisms to inoculate the soil around the root with a good set of organisms. Additional water can be used. The larger the drop size. boom sprayers. most likely resulting from the lack of oxygen in the liquid.typically at 5 gallons to the acre (50 L /Ha) per 1 to 6 feet of plant canopy. back-pack sprayers. through to senescence of all plants in late fall in temperate zones.
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. Coverage of leaf surface is the critical measure. however. the organisms will smash into the leaf or stem surface and disintegrate. although numbers of active and total organisms falls off at an ever-increasing rate. Tea can be applied to foliage as a foliar spray . Tea should be applied during weather when plants are active. An important point is that the tea cannot contain particles which will clog the water delivery system. then the tea will remain aerobic for 6 to 8 hours. however. Sprayers are ideal for applications of tea onto leaf surfaces. testing indicated that tea needed to be made and then used. Other methods of root zone feeding vary from simple hose-end sprayers to elaborate drenching systems that dose each plant with a pre-measured amount of solution to injection systems. Tea can be applied to soil as a drench.on both sides of the leaves. helicopters or airplanes. can be applied with water in any of the many ways water is applied. and not drip off. It should be clear that if organisms are delivered to leaf surfaces at too high a velocity. once per growing season. every two weeks. a tenfold reduction in numbers. It should be clear that with injection systems. A good mist is desirable. Inc. This means they will not be present to protect the leaf surfaces or occupy infection sites instead of the disease-organisms. and in tropical areas. typically at a pint to a quart per plant of undiluted tea. hoses. we showed that if the tea is well-aerated. No more than 60 to 100 psi should be used to spray out organisms. the more likely the tea will run off the plant. drip irrigation lines. When the first commercial brewer (Microb-Brewer) was released. 1995). When applying compost tea to leaf surfaces. stem and flowers of the plant. through pivots. but a light mist often helps the organisms establish a foothold on the leaf. Do not apply tea when it is raining hard. At the end of three days. Low volume sprayers with moderate pressure are the best suited for tea application. This is acceptable for a soil application. when the plants need protection. the key is getting at least 70% of the leaf covered with the tea organisms . or when needed to occupy leaf surfaces and compete with disease organisms. Sprayers range from tractor mounted models for large acreage to simple backpack versions. typically 15 gallons to the acre (150 L/Ha) in whatever amount of water is desired. they should not hit surfaces at more than 20 to 80 psi. With further testing. but not for a foliar application. For example. the pressure applied cannot smash the organisms into the soil particles. How Long Can Tea Be Held? This is an area currently being researched. If. This means starting at two weeks before bud break. then holding time can be increased. emitters. and therefore must be properly screened to pass through the spray nozzles. Tea should be applied so the liquid will remain on the leaf. aerobic activity falls rapidly. with the right set of organisms present. etc.

If bacterial and fungal foods are added to the tea at 48 to 72 hours. DNA fingerprinting showed that nearly 50% of the species of bacteria or fungi being examined were lost when 3% phosphoric acid was added to initiate dormancy in the active organisms. Certain materials can be added to tea to push the organisms into dormancy. For example. again. This is because very few of the organisms that live on leaves grow in any plate count medium. If disease is observed. Tea is not a panacea that will cure everything. The organisms in a tea MUST be dormant if the tea is placed in a sealed container. but adding food resources will likely out-strip the ability of aeration to maintain aerobic conditions. then the activity of the organisms can be extended. generally the infected foliage has to be drenched with maximum amounts of tea every three days until the disease is controlled. A single application of un-diluted tea immediately applied slowed the mildew down. etc. although there was no spread of infection. when the infestation was severe. Three days later. make a tea and spray immediately onto the affected areas. This yard receives no pesticide or inorganic fertilizer applications. No black spot or mildew was observed throughout the summer. however. dormant individuals. In fact. leaves that contained very few active organisms and leaves that contained a high number of active organisms gave the same plate count numbers. Already wilted leaves could not be brought back to life and were removed. in the author’s yard. but did not get rid of it. in fact. applications for preventative control of foliar diseases are 5 gallons of tea per acre (50 L/Ha) every two weeks. The best thing is to keep the tea in the maker. The mechanism for protection has to be understood. as long as 5 gallons per acre (50 L/Ha) is applied. including spores. teas which are “put-to-sleep” are better for soil applications. But mildew was noticed on the roses in July 2000. but still of interest. by concentrating applications of organisms on infected. but aeration must be continued. none until mid-July. and a similar number of spores appeared to be present on each set of leaves. This suggests that even once disease appears. recovery is possible. More testing remains to be performed however on this point. Put-to-sleep tea. more diverse teas. the 5 gallons (50 L) can be diluted in however much water is desired. depending on the number of active organisms. the organisms must be immediately active to protect the leaf surface. drenching the area. Thus. 2000. but not yet dead areas. Typically this results in protection of the leaf surfaces by the tea organisms and the disease is consumed or out-competed. Control of Existing Disease Conditions. and still. steams. Tea must be applied to both top and bottom of leaves. In a few cases. For preventative applications. Typically. During the incubation of the plates. repeated application was required to bring back the condition of health. a second application was made by drenching the infected areas with undiluted tea. admittedly not a replicated study. or the respiration of the organisms will cause the bottle to expand and perhaps explode. By the end of five days total. and continue the aeration if it becomes necessary to add food to maintain activity of the organisms in the tank. came to life on plate media. a serious reduction in diversity of the organisms occurs. as well as active organisms to grow. so these teas would be less likely to benefit plants than younger. the problem was not controlled. how much food was present in the tea recipe to begin. a single application of undiluted tea was made to the roses on May 15. a full year and three months after the single application. and the number of organisms extracted. starting at two weeks before bud break and continuing until all danger of loss of crop yield due to disease is past. but not guaranteed.
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. Any large tank with aeration can be used to hold the tea. whereas on leaves. A third application of undiluted tea. blossoms. Plate count assessments cannot be used to determine this kind of information since plate counts allow spores and dormant individuals. and tea correctly applied to deal with the CAUSE of the problem. To control already existing foliar diseases. 1999. Addition of foods to tea can help maintain shelf life of a tea. because the organisms have time to wake up before they have to start to function. in a recent test. which may be a reason that a single application was effective for more than a year. Foliar Applications. or sprayed directly into the top layer of soil. Recent work by John Buckerfield in Australia indicates that coverage with a mulch layer improves organism survival (most particularly earthworms if they are applied in worm compost) and increases the benefit of single-applications. three days later controlled the mildew to the point that no visible symptoms were apparent.

green leaves. take another soil sample for analysis to make certain the organisms survived application to the soil (total biomass gives this information). The organisms will supply the micro. or humic acids for fungi. Compost tea should contain nutrients to feed the bacteria and fungi. the recipe chosen should enhance bacterial biomass in order to balance the fungal-to-bacterial biomass ratio.Soil Applications. Apply a tea with organisms that will degrade common pesticide residues. but not active. that you need to know something about your soil. then the soil is likely to be fungal-dominated. Soil rich in organic matter with a healthy foodweb will be adequate for plant growth. then only the specific foods are needed. to balance the fungal-to-bacterial biomass ratio. a sample of soil must be taken and the foodweb assessed. In this case. a low organic matter soil will require a compost or compost tea with high numbers of beneficial microorganisms. The plant will feed those organisms. Then. straw. in a form that is easy for the plant to take up. however. After 2-4 weeks. and the plant feeds the organisms needed. as well as micronutrients that the plant can absorb. such as sugars for bacteria. Conversely.and macro-nutrients that the plant requires.g. Compost or compost tea will supply the organisms that do the work the plant needs. Always consider.
Compost Tea Appropriate to the Plant
The requirements of plants for the organisms that most benefit their growth need to be recognized. make a tea that is appropriate to return the missing organism(s) to the soil and apply at 5 gallons to the acre (50 L/Ha). Soil lacking organic matter will need a good set of beneficial microorganisms and food to feed those organisms in order to get good plant growth. carbohydrate material. bacteria and fungi to protect the plant from disease-causing microorganisms? Does the plant require nutrients to be retained in the soil around the plant? What is needed to make those nutrients available back to the plant? Which organisms decompose any toxic or leftover residues that may be present in the soil? How can I build soil structure so air diffuses into the root zone and prevents fungal root rot diseases? How do I improve water-holding in the root soil? How can I get the roots of my plants growing down 5.
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. to 10. such as woody materials. bark. as well as sugars. protozoa and beneficial nematodes. For example. If the organisms are not present. A tea less rich in food resources can be used in this instance. Chemicals that kill the beneficial bacteria and fungi on the plant’s leaves. no matter how large or small the area involved. stems and blossoms need a compost tea containing those microorganisms in order to replenish the plant’s defenses. even in soils high in organic matter. fresh manure). a chemical residue is indicated. The organisms needed by different plants can be supplied by applying compost and compost tea. if the organic matter in the planting medium is not slow to decay (e. soluble kelp. should ask: “What does the plant require in terms of nutrients. and they had food to stay alive (activity gives this information). Compost and compost teas need to be defined relative to the specific plant and soil to which they are applied. then the tea recipe should be one that selects more for fungal biomass. Growers of plants. There are different organisms for different plants. Compost and compost tea will increase the diversity of bacteria and fungi. oak leaves or conifer needles). to 15 feet deep into the soil?” The answer to the above questions always lies with the soil organisms. humic acids and algal exudates to increase the food resources for the microorganisms. if the soil is high in humic acids and other recalcitrant materials (those resistant to decomposition or decay. again. green residues. with the foods those organisms require to decompose resides. and needs to be remediated. To protect against soil diseases reaching the roots. Similarly. old manure. If the right organisms are present. regardless of sand/silt/clay ratios. Just because a soil has lots of organic matter does not mean the full complement of organisms beneficial to the plant are present.. Compost tea can also contain nutrients that plants can take-up through the foliage.

Turning becomes critical for cooling the pile and bacteria are selected as fungi are killed during the turning process. significant benefit to plant production was observed. syrups such as molasses. and thus alleviates nutrient stress if plants are lacking these nutrients. Thus. compost high in fungal biomass should be chosen. then the N in that material is more readily available to the microbes. the bacteria will bloom. It is critical to start with compost or vermicompost that will produce the desired microbial balance. sterilants. piles without the high N and with more woody material typically do not reach temperatures above 150° F (65° C). controlled scientific studies are required. alcohol. then add the liquid to the water at the start of the brew process). increasing temperature and rapidly using up the oxygen. In each instance. The Right Compost. the size of the particles in a compost pile is important. To prevent anaerobic conditions. N and K. Turning is needed only to homogenize the pile and spread the growing organisms evenly throughout the materials. the faster the pile heats. phenols. sugar beet syrup. benzene.The balance of fungi to bacteria must be viewed with respect to the needs of the plant. benzoate. Comfrey has been chopped and added to the compost before it is composted. such as antibiotics. Generally. For example. compost high in volume of woody material (resistant to rapid decay) will probably be fungal-dominated. ADD NOTHING THAT CONTAINS A PRESERVATIVE!! What are preservatives? Anything we use to prevent microbial growth. fumigants. Additives that help bacteria most are simple sugars. or other high cellulose containing pulp material. and may combust. while row crops and grass need an equal balance of fungi to bacteria. A typical fungal compost recipe contains 25% manure. while soluble kelp (surface area) and humic acids (foods) enhance the growth of fungi. If green or woody material is finely chopped. Anecdotal information from growers suggests that comfrey is high in Ca. and yeasts (vitamin addition). 45% green material and 30% woody material. Simple sugars to encourage bacteria growth. as well as protozoa. If too much N is present. Again. Based on the limited testing that has been done. churn the leaves in the bucket for a day or so. Materials that help fungi more than bacteria are things like fruit pulp (the cellulose in the pulp generally helps fungi more than bacteria but bacteria will grow on the sugar portion of the pulp). If the tea needs to be more fungal. Each composter needs to work the best combination out for themselves. to the compost basket during the tea brewing operation. we have determined that teas applied to foliage should always be bacterial in nature. trees require a fungal-dominated soil. Fungal composts typically need less turning because the chunkiness of the woody material allows better air diffusion. can be made by adding components to the tea solution before the tea brewing process begins. The higher the level of N in the manure. nettle or dandelion “soups” can also be added to enhance the micronutrient content of a tea. or as a brewed soup (stuff a bucket full of comfrey leaves. However. cane syrup. compost with finely chopped material will require air to be pumped in or turned at least once per day. The quantity and source of manure is important. apple juice from applesauce production. chlorine. Plant extracts. or after composting is finished (dangerous if there is any disease on the comfrey that could spread through the compost). If bacterial tea is indicated. spoiled carrot juice. terpines. When in doubt. ASK! The selection for the preferred microbial community. the pile may heat above 180° F (85° C). use compost made with 25% manure. humic acids. iodine. and to fully accept this type of work. etc. such as comfrey. given a compost of say equal bacterial to fungal biomass. 30% green material and 45% woody material. soluble kelp (protein and micronutrients). make a tea that contains both bacteria and fungi. The Right Foods. most likely explained by improved Ca uptake by the plant. If you aren’t sure what your plants need. and let the plant do the selecting. with their own starting materials). these were not replicated studies. add water.
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.

can drive teas anaerobic! 0. test in your system to determine effect 1 to 15 oz. Barley meal. and plants Fungi (some bacteria)
Application Rate per 50 gal (200 L) of tea
600 ml (1 pint) to 4 L (1 gal) 0.1 to 1% 0. but isn’t right for your indoor citrus tree. powder Spices / Garlic. champagne) Yucca / Desert King. orange oil. or sometimes be detrimental. soy Vitazyme / Vital Earth Resources Yeast (brewers.
Group Fed
Bacteria at low concentrations. vitamins for both bacteria and fungi. etc Rock dust. EXAMPLES of Food Resources for Different Organism Groups. Organic Gem Fruit Pulp Humic acids / Terra Vita. cinnamon. look at the mineral needs of the plants Test in your system 1 to 5 oz Test in your system 100 to 600 ml (beware of foaming!)
*1 US gallon = 3. onion oil. The special elixir that works wonders for one grower may have little or no benefit. Oatmeal. the soil. fungi at high concentration (syrup) Bacterial foods. materials like garlic oil. The biology may have been right for your friend’s squash. to other plants. citrus. Feathermeal. Helena Chemical Co. then bacterial food is released) Fungi (some bacteria) Fungi Mineral nutrients for all organisms. or in a small area of your field.8 L. The explanation lies in the biology and the chemistry of the plant.01 % to 1%. coli counts in teas. add carefully.Use cold-water grown kelp. cinnamon. Cold-water kelp absorbs and retains more nutrients during growth than warm-water kelps. wine.
Product Name/Company
BACTERIAL Simple sugars Kelp Fish Hydrolysate / Neptune’s Harvest. orange oil. citric oils. Fungal surfaces Fungi. scales and cartilage liquefied using enzymes. and the tea. Eco-Nutrients. When in doubt. Testing needs to be performed. onion. Table 9. or round up to 4 L
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. \ Many interesting ingredients have been used in teas. Some spices have properties that inhibit specific microbes. resulting in greater micronutrient benefits. important to have bones. oregano. minerals. not heat or acid Fungi and Bacteria Fungi (as humics broken down. While a great deal more testing is required to document efficacy. not warm-water grown kelp. test the tea on part of the plant. depending on product
600 ml (1 pint) to 1 gal (4 L) Test in your system Test in your system.1 to 1%. and oregano have been reported to reduce E. but their benefit has rarely been documented. lemon. surfaces for fungi Inhibitors of specific microbial groups Fungi Complex mix of proteins. Hydrahume FUNGI Humic acids (see above) Protein Meals / Soybean meal. bakers.

bacteria usually are fine Check mycorrhizal fungi. Thus. 2. Use their food kits until you can assess the effect of adding or subtracting food resources using. cabbage. many brassicas). see below). make certain that adequate aeration is provided or the tea can become anaerobic within just a few hours. 1. rhododendron. For example. Category of plant that is closest to the one you want to grow. With high amounts of sugar. cabbage. peach. fungi most likely to be seriously lacking Compaction is tough to overcome. check mycorrhizae
Sand
Loam
Clay
Most plants can be colonized by mycorrhizal fungi. Soil type that is closest to the three listed in the table. Ingredient amounts should be maintained at the same ratio per volume of water as in the following recipes. a light microscope. cole (strongly bacterial) Need both bacteria and fungi to build good soil structure Need to improve bacteria significantly. avocado and olive. A reasonable investment is learning to use a microscope to recognize the sets of organisms. Epiphytic plants and palms most likely fall in that category as well. Grasses (slightly bacterial) Need mostly fungal activity. for example. since fungi are most likely lacking Need to improve both bacteria and fungi. There are two parameters to consider in Table 10. fungi need to be helped extensively Check Ca:Mg. fungi need maximum help.e. some fungi needed Need mostly bacteria to form microaggregates and get nutrient cycling going Row Crops. mycorrhizal colonization of roots should be checked by taking root samples from several plants and sending them into a soil biology lab (such as Soil
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. and snowbrush fall in the berry/vine/shrub category. check Ca:Mg ratio Deciduous Trees.
Soil Type
Broccoli. even if compost volume is not linear. grapevines.. some bacteria to build soil structure Need both bacteria and fungi to build good soil structure Need both bacteria and fungi. fungi need maximum help Conifers (100+ more fungal than bacterial) Mycorrhizal fungi usually needed. almond. Conifers include pines and most evergreens. while strawberries. Table 10. Vines (2 – 10 times more fungal) Help fungi to the maximum extent. look for hydrides. Most other plants either do better in low nutrient conditions or are obligately mycorrhizal. improve fungi to maximum amount Maximize fungi. For those who wish to test the impacts of different foods on organism growth. It should be noted that some cedars actually fall in the deciduous category. Deciduous trees include poplar. kiwi. the following recipes are based on 50-gallon (200 L) compost tea making machines. tomatoes are in the grass/row crop category. The same amount of food per unit liquid is still required. apple. coffee.Recipes
Most compost tea machine makers have food kits that match the aeration abilities of their machines. most kales. cauliflower (i. check Ca:Mg ratio
Plant types
Berries (Equal bacteria and fungi) Need to help fungi to the maximum. The Kind of Tea Needed for Different Plants and Soil Types. regardless of the inoculum amount (which is not linear. citrus. since fungi are most likely lacking Need to really push fungi. except for strongly bacterial-dominated plants such as broccoli.

and observe the biology in the tea. Fine-Tuning Your Recipes. If the container with double or triple amounts had highest organism’s biomass. If brewed too long. A very small amount of compost might be acceptable. then the product is detrimental. To the next container. at the same time. Then make a tea with 5 pounds. and check the biology again. the optimal amount of compost has been found. or three or more clean containers. Extraction efficiency does not relate to the volume of water used for extraction but rather to the efficiency with which the water pulls the organisms from the compost. such as just kelp and a little molasses. Water versus Compost Volumes and Extraction Efficiency. or the soil to which the tea was added. and look at what is in the tea at 8 hours. www. the microorganisms may go to sleep and not be active. When the number of organisms in the compost does not increase from one amount to the next higher amount of compost. Follow directions on labels of various products for most food resources. Let them brew for 24 hours. Commercial versus Indigenous Organisms. To the “control” container. If a tea turns out well. To the next container. 24 hours and 48 hours. the particles of compost move against each other and organisms are pulled from the compost. Lower pressure is acceptable if. to determine the percent of the root system colonized by mycorrhizal fungi. Use the Qualitative assessment methods until you have your recipe determined. If mechanical parts can clog.
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. Test products to determine whether they are helping to grow organisms. using the qualitative assay. One way to get the indigenous beneficial microorganisms into the tea is to add a pound of soil from highly productive soil or composts to the compost container. Make a tea with minimal additives. mycoroots@attbi. take soil from the surface near an existing healthy plant growing in a native system and use this as an inoculum. non-soluble materials should be placed in the compost container. For Example: Run a tea brew with 1 pound of compost in the machine. and then test your own machine to determine what amount of compost gives you the best extraction. Initially use the compost amount recommended by the person you buy the tea machine from. and movement of the compost in the container. The brewing time must be long enough and/or have enough mixing to extract the desired soluble nutrients (food resources used by the microorganisms and micronutrients). Then add triple to a fourth container of tea. the compost has to be free to move in the container. or for other plants with limited species requirements. or Efren Cazares lab. not at the beginning. Be sure the soil has not had recent inorganic fertilizer or pesticide applications. Deciduous trees require VAM inoculum. then that tells you which amount to test in the real tea brews. Thus. 30 pounds. Place the same amount of tea in each of two. or a combination of VAM and ectomycorrhizal fungi.soilfoodweb. add only water.com. because the spores will begin to germinate in the tea after several hours. equal to what you add with the product you are testing. or are harmful to them. if the extraction conditions are optimal with respect to water flow THROUGH the compost. Brewing Time. while conifers need ectomycorrhizal inoculum. as an inoculum for the next batch of tea. When to Add Materials. Which amount of product had the highest biomass of bacteria and fungi? Protozoa? Nematodes? If the control had the greatest. Blueberry needs ericoid mycorrhizal fungi.Foodweb Inc. add the smallest amount of the product possible that should have an effect. In this case. save a small amount of the tea. but no inoculum of these mycorrhizal fungi is available commercially. Soluble materials should be added to the water at the beginning of the brew cycle.. Indigenous microorganisms are clearly the best choice for any particular system. Let the organisms have a few hours to grow before testing. Then 10 pounds. This will keep improving the beneficial microorganisms. 20 pounds. Mycorrhizal spores are sensitive to pressure just after they germinate and the pressure involved with mixing will kill them. unless otherwise noted in the recipe. therefore develop beneficial microorganisms adapted to your conditions. etc. Mycorrhizal spore suspensions should be added to the tea at the end of the brewing cycle. add double that amount.com.

e. Mycorrhizal Inoculum The concentration of spores needed has not been well established for different plant species. add a greater amount of dry molasses.The following recipes are all based on 50 gallons of water. Of course. Dry molasses lacks a significant component of more complex sugars. proteins. maple syrup. The Basic. injection system. or starch. Bacterial Tea (based on 50 gal tea maker) 15 pounds (7 kg) bacterial compost 16 ounces (500 mL) black strap molasses (Dry molasses does not substitute) 8 ounces (250 g) soluble cold-water kelp (additional proteins) 1 to 6 ounces (30 to 200 mL) liquid. plant-beneficial compounds during the brewing process. although these grainy materials can harm mechanical pumps. Addition of kelp adds micronutrients and some bacterial as well as fungal food.. rather than a limited set (i. Equal Ratio Fungi to Bacteria Tea (based on 50 gal tea) 15 pounds (7 kg) 1:1 fungal to bacterial biomass ratio compost 16 ounces (500 mL) humic acids 8 ounces (250 g) soluble kelp Fish hydrolysate. so an emulsion is more beneficial as a bacterial food than a fungal food. etc. and deciduous trees. or other high complex protein materials (see label on packages). add the spores to the spray tank. additional proteins Add nothing with a preservative or antibiotic in it! Make sure the compost is mature and has not been disturbed or turned for a week or more. while conifers and some late-successional deciduous trees require ectomycorrhizal fungi. Starting-point. holding tank. fish emulsion Add nothing with a preservative or antibiotic in it! Concoctions that become anaerobic can be added to recipes like this one that call for plant extracts. but any fungal food could be substituted here. so if using dry products. so use a second type of sugar such as corn syrup. vesicular-arbuscular mycorrhizal fungi (VAM) are the mycorrhizal fungi of choice. the brewing process must remain highly aerobic. Since mycorrhizal spores germinate and begin to grow within a few hours of addition to most teas. fruit pulp Add nothing with a preservative or antibiotic in it! Humic acids select for beneficial fungi. shrubs. 3 to 5 humic acids). vegetables. filtered plant extract material (for example. degassed if required to remove chlorine. Fish hydrolysate should be tested for their ability to serve as fungal food resources before using extensively. fruit pulp. This yields a moderately bacterial tea. so use a machine or method that provides a high rate of aeration and thorough mixing. oatmeal. soybean meal. fruit juices. For row crops. most berries. nettle soup. dandelion wine. A range of 50 to 100 spores per gram soil is probably adequate to establish colonization. feathermeal. because the anaerobic decomposition products will be consumed and converted into aerobic.
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. and checked for extraction of the compost (brown color released into brew before adding molasses or kelps). rock powders. Fish emulsions do not have the oils that help fungi grow. yucca extracts. 8 ounces (250 g) soluble kelp. 8 oz (250 g) Fish hydrolysate. There are fewer types of sugar in dry molasses. grass. or rock flours can be beneficial as well. Make certain to obtain a mixture containing many humic acids. comfrey tea). Rock dusts. Fungal Tea 20 pounds (9 kg) fungal compost 1 pint humic acids (600 mL) 4 oz (100 mL) yucca high saponin content).

2000 in Frankfurt.com updates and links to compost tea production. Check the Soil Foodweb Inc web site. 5 Speaker: Troy Russell. There were 3 replications. humic acid.soilfoodweb. A field trial was conducted at Wichita. Tomato cultivar Merced was used and individual plots consisted of 5 plants grown on beds covered with red plastic mulch and supported by stake and weave system. Bandon. Kansas during Summer 2003 to evaluate the potential of pre-plant compost. C. we would like to have people check the SFI e-zine. E.. N. The other components of this system are minerals. A split plot design was used with fertigation treatments as main plots and the other two factors as sub-plots. fungicide (Dithane) or water. I feel confident and am happy to share those experiences with you. materials were applied that would bring the natural system back into place most rapidly. 97411. made using an aerated brewing process. the use of compost. required a natural approach on the golf course practices. which contains humic acids. and Tisserat. OR. fish emulsion and yucca extract and applied to plots starting 2 weeks after transplanting. Kansas State University Suppression of Septoria Leaf Spot Disease of Tomato Using Aerated Compost Tea ASHS 2004 annual meeting. but there was a significant effect due to foliar sprays. for example.A. Superintendent at Bandon Dunes Resort. or call us to learn more about local tea production and tea centers. and in an environmentally protected area. not just bacteria – in the tea and showed the tea they made was in good to very good range. Gangaiah. a wide spectrum of beneficial microorganisms and last but not least. www. Septoria leaf spot of tomato.3%) and fungicide-sprayed plots
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.ashs. USA ABSTRACT: The unique location of the BDR in the dunes. have been reported to have potential for controlling a range of plant diseases and improving crop health. 1. caused by the fungus Septoria lycopersici. Disease incidence and severity were recorded weekly for 3 weeks following the appearance of disease. Aerated compost tea was brewed weekly using a vermicompost-based recipe including alfalfa pellets. fertigation with CaNO3 or compost tea. is a common and destructive disease of tomato in Kansas. Instead. to control Septoria leaf spot of tomato. right at the Pacific Ocean. and compost tea applied as a foliar spray or through drip fertigation. organic matter. check results and gain reproducible results and experiences.lasso Poster Board #292 Abstract: Compost teas. To return the system to the most natural system. As result. The basis of our NGCP (Natural Golf Course Practices) is founded on the properties of the most natural system. Plots were harvested twice weekly and counts of No. The experimental design included three factors: Pre-plant application of 13N–13P–13K or vermicompost. There were no effects of pre-plant or fertigation treatments on Septoria leaf spot disease. suitable for easy golf course or management. which can be added as organic or inorganic forms. Dec.org/annualmeeting/conference/index. and foliar spray with compost tea. with mean severity of compost-tea-sprayed plots (26. --------------------------------------------------------------------------------------------------------------------------------Two student posters. molasses.
Scientific Papers or Abstracts
Experiences in Natural Golf-Course Practices at Bandon Dunes Resort
Presented at Golf Consultants International. Carey. No 2 and cull grade tomatoes were recorded. After gaining a 2-year experience. The challenge was to research what natural practices are available and carefully apply. http://www. the first where they actually determined the biology – all of it. The challenge was to copy nature on an industrial scale and in a fashion.Grower Experiences
In the past examples of experiences that growers have had with compost tea have been put in the manual. the tea suppressed disease.

(31. lysozyme. Treatments included 1) a control. Producing ACT with a molasses-based additive inconsistently suppressed damping off. and Mahaffee. 0. However there has been limited investigation relating disease control efficacy to various compost tea production methods. k. and 2) compare the efficacy of organic fungicides with conventional fungicides to control S. Utkhede. 10 g/l. the whole food web. there was no significant
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. ---------------------------------------------------------------------------------------------------------------------This is an interesting paper.9%) at trial termination. 2004. Experiments were conducted to determine the effects of treatments on Clavibacter michiganensis subsp. M. including Septoria lycopersici common in tomato production. A follow-up greenhouse experiment is in progress and will be presented with the field data. and plants in these treatments were as tall as those observed in untreated uninoculated control plants.3 g/l. respectively. Concerns have been raised regarding the use of Cu fungicides. particularly compost tea produced using active aeration and additives to increase microbial population densities in compost tea. There are other things in this world than just bacteria! Scheuerell. and Gleason. Across all compost tea samples. michiganensis in vitro and on young seedlings inoculated with the pathogen under greenhouse conditions. 2004. 49: 305-315. 2) a conventional treatment in which fungicide applications of Bravo plus Cu and Quadris plus Cu were alternated. Compost tea is being used increasingly in agricultural production to control plant diseases. have the ability to prevent the incidence of bacterial canker of tomato plants caused by C. Treatments with B. i.. just might have something to do with suppression. s. subtilis (Quadra 136) and Trichoderma harzianum (RootShield(R)). and Koch. Helland. Rhodosporidium diobovatum (S33). C. They rather miss the point that fungi. Compost Tea as a Container Medium Drench for Suppressing Seedling Damping Off Caused by Pythium ultimum. and 0. Biological treatments to control bacterial canker of greenhouse tomatoes. Tomato plants treated with lysozyme at 10 g/l and 100 g/l showed significantly higher plant height compared with the inoculated control plants. Iowa State University Control of the Foliar Disease. h. BIOCONTROL. because of their potential to cause plant damage and toxicity to beneficial organisms. R. concentrated. michiganensis under greenhouse conditions.e. Septoria lycopersici. evidence suggests that residual nutrients can interfere with disease suppression. protozoa and nematodes. Lysozyme was bactericidal at 10 g/l concentration in vitro. The objectives of this research were to: 1) investigate the efficacy of compost tea made from either windrow composted cattle manure (WCCM) or vermicomposted cattle manure (VCM).6 g/l. in Organic Tomato Production Poster Board #290 Abstract: Disease management in organic tomato production poses one of the greatest challenges for organic producers in humid climates. Effect on damping off ranged from not suppressive to consistently suppressive depending on the method used to produce the tea. W. 4) Serenade TM Fungicide (Bacillus subtilis). 1 x 10(9) CFU/ml. Disease pressure was mostly from the bacteria speck/spot complex. Disease severity was significantly (P < 0.9%) significantly lower than water-sprayed plots (45. 2 and 3). subtilis (Quadra 137) applied as a spray at 0. michiganensis subsp. Aerated compost tea (ACT) and nonaerated compost tea (NACT) produced with or without additives was investigated for the suppression of damping off of cucumber by Pythium ultimum. Both organic and conventional tomato growers have relied on copper (Cu) fungicides to control many diseases. Phytopathology 94:1156-1163.. vermicompostea. No assessment of the biology in this one – did they actually make good tea? Joslin. 3) copper fungicide (Champion).05) reduced and marketable yield was 60% higher with the two Cu treatments (No. and 6) VCM compost tea. The most consistent formulation for damping off suppression was ACT produced with kelp and humic acid additives. S. It is the basis for the NOP being paranoid about molasses.5 g/l. 5) WCCM compost tea. Heating or diluting compost tea negated suppression. B. ------------------------------------------------------------------------------------------------------------------------The following shows that having mixes of organisms can result in disease organism suppression. compared to other treatments. Taber. lycopersici in organic tomatoes. Compost tea was used to drench soil less container medium inoculated with Pythium ultimum.

B. regrowth was also dependent on the type of starter compost material used. applied as foliar sprays on tomato transplants. E. However for all ACT produced without the molasses-based additive. including bacterial spot.J. Using disease outbreak strains marked with green fluorescent protein (GFP) and spontaneous antibiotic-resistance. foliar sprays with compost water extracts did not reduce the severity of foliar diseases.A.A. H. Amending plot soil with several rates of composted yard waste did not lead to additional control of fruit disease over those only sprayed with extracts. COMPOST SCIENCE & UTILIZATION. What proof did they have that the “composts” they used were even composts at all? Al-Dahmani. and hoping it will cure your headache. No one in their right mind would produce compost tea in a sealed container such as used in this “research”. coli populations increased from I at time 0 to approximately 1000 CFU ml(-1) in both types of tea by 72 h. or 7 log base 10 CFU) above which compost teas were suppressive. For Salmonella. Extracts prepared from composted cow manure. particularly produce intended for fresh consumption. raising public health concerns about potential contamination of treated crops. -----------------------------------------------------------------------------------------------------Note in the following paper. Salmonella populations increased from 1 at time 0 to over 1000 CFU ml(-1) in dairy manure compos! t tea with 1% molasses. P. we found that regrowth of Salmonella enterica serovar Thompson and Escherichia coli O157:H7 was positively correlated with molasses concentration. and Stanker. or composted yard waste. particularly molasses. During the 1997 season. an organic farm compost. total cells or CFU with disease suppression. vesicatoria in infected leaves was reduced significantly by extracts prepared from composted cow manure. S. largely because of their disease suppressive activity when applied to foliage or soil. Pathogen regrowth did not occur when molasses was eliminated or kept to 0. foliar sprays with compost water extracts significantly reduced the incidence of bacterial spot on tomato fruit. Suppression of bacterial spot of tomato with foliar sprays of compost extracts under greenhouse and field conditions. We have found that molasses amendments also favor regrowth of human pathogenic bacteria. 1998. Efficacy of the water extracts was not affected by oxygen concentrations in the suspension during extraction. Foliar sprays with a mixture of chlorothalonil and copper hydroxide or with acibenzolar-S-methyl reduced the severity of bacterial spot as well as incidence of spot on fruit. 12:93-96. L. J. or sterilization by filtration or autoclaving.A. ----------------------------------------------------------------------------------------------------Ingham. -------------------------------------------------------------------------------------------------------------------------This is one of the two “papers” used by the USDA to support their statement that compost tea should be viewed as being raw manure.000 CFU ml-1 in chicken manure compost tea by 72 h. The population of X. Anaerobic bacteria and compost tea.. compost maturity. S.2%. 2003. 2004. Compost water extracts (compost teas) are gaining popularity among organic growers. In the field in two growing seasons. when the severity of bacterial spot in the field was high. E.48 log base 10 total cells per ml. What was the point of these people’s work? Trying to discredit the growing industry of compost tea? Why would any this “journal” accept such an inaccurate paper? Duffy. C. Miller. Production methods often include addition of supplemental constituents.. Rather like throwing a handful of dark stuff in water. there was a threshold of bacterialbased population density (6 log base 10 cells per ml. Abbasi. BioCycle 39: 86
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. they do not in any way determine what is in the “compost extracts” that they prepared.. and Hoitink.H. resulted in a moderate but statistically significant reduction in the severity of bacterial spot. The efficacy of foliar sprays with compost water extracts (compost extracts) in reducing the severity of bacterial spot of tomato caused by Xanthomonas vesicatoria was investigated. Sarreal. to stimulate plant-beneficial microbial populations. PLANT DISEASE. 7.relationship of bacterial populations measured as active cells. Effect of molasses on regrowth of E-coli O157 : H7 and Salmonella in compost teas. The degree of control provided by foliar sprays with the most effective compost extracts did not differ from that obtained with the plant activator acibenzolar-S-methyl. and from 1 at time 0 to over 350. composted pine bark. Ravva. 87:913-919.

. Ingham. variables in producing and applying such compost teas are considered.H. Making a high quality compost tea. J. both organic and inorganic. M. The maturity of the compost and the nature of its source constituents are major factors in the effectiveness of compost tea treatments. --------------------------------------------------------------------------------------------------------------------------------Blair. These include the mesh size of the bag or filter. is diluted with an equal volume of dechlorinated water. E. S. 2001.2001. . BioCycle 40: 74-75. 1996. Using help from various
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. that are present in the compost. storage. and application methods. In the writer's opinion. and Jimerson. Investigations into liquid compost extracts. The eventual goal is to recycle 100 percent of the organic waste produced in the park. Compost tea is a liquid extract of compost that contains all of the soluble nutrients. Karin. thereby saving the Presidio Trust $100. --------------------------------------------------------------------------------------------------------------------------Scheuerell. V.000 square feet every 2 weeks. BioCycle 41: 71-72 The potential benefits of compost tea. W. Understanding How Compost Tea Can Control Disease. E. BioCycle 42: 51-52 The benefits of a composting project at the Presidio. suppressing both the germination and the growth of plant pathogenic organisms. T. Compost teas coat plant surfaces with live bacteria. BioCycle: 40: 94 . The elimination of anaerobic conditions and the products of anaerobic metabolism are also discussed. The benefits provided by the tea depend on what can be extracted from the compost. fungi. as long as they are not growing. Sustainable practices thrive in a national park. The performance of these solutions depends on their preparation. protozoa. BioCycle 44:22-23.000 per year. A. 2000. Composters are concerned that the presence of bacteria that can grow without oxygen or in a low oxygen environment poses a problem in compost or compost tea. so the practical benefits of using compost tea to suppress root diseases may be marginal. 1999. and a large portion of the organisms. it is very important that the tea contains organisms. Murray. Part II. The writer discusses the major factors that influence the quality of compost tea. 2003. -------------------------------------------------------------------------------------------------------------------------Brinton. such as bacteria. The writer discusses compost tea. which is part of the Golden Gate National Park in San Francisco. --------------------------------------------------------------------------------------------------------------------------------Wickland. The effects of a compost tea trial on golf course greens in San Francisco over a one-year period yielded positive results. steep time. control plants had a greater incidence of disease than plants treated with aerobic tea or anaerobic tea. and Koch. statistical differences did not emerge until 6 to 8 weeks after germination. Golf Courses Find Value in Compost Tea Programs. a range of different preparations made using compost as a starting material and producing a liquid extract or a liquid version of the original compost. In April 2000. BioCycle 37:68-70 In a review of the use of liquid extracts of compost for the control of pathogenic fungi in plants. J. M. Part I. microbiology. BioCycle 42:6466. which can be inconsistent from batch to batch. The tea is brewed in two 100-gallon and one 25-gallon brewers from Growing Solutions. protozoa.The writer discusses anaerobic bacteria and its impact on plant growth. are discussed. and water recirculation and aeration. Factors contributing to a wide diversity of bacteria. and nematodes desirable in compost tea are also addressed. Tränkner. California. and nematodes. and applied at a rate of 2 gallons per 1. However. Understanding compost tea. are discussed.F. In 2 of the 3 trials. The Presidio Trust took on the composting project for economic reasons and is now reaping the benefits. 1999. fungi.. BioCycle 44: 20-5 ---------------------------------------------------------------------------------------------------------------------------Grobe. The writers discuss the combined efforts of Washington State University Cooperative Extension and a Whatcom County grower to evaluate compost tea in the suppression of plant diseases. Bess. A major advantage of compost tea is that it can be applied through the irrigation system or through a spray rig. Ingham. Alison Kutz-Troutman of Cascade Cuts gave the university an opportunity to test the efficacy of compost teas as a valuable integrated pest management strategy. . compost quality. San Francisco's Integrated Pest Management program is using compost tea as an effective tool for suppression of turf diseases as well as overall reduction of synthetic fertilizers. and Droffner. the presence of bacteria is not a problem. L. Brewing up solutions to pest problems. 2003. What is compost tea? Part I.

Two Northwest companies are working toward the large-scale production and supply of compost tea-Growing Solutions Inc. Recipes and uses for the quality compost were found. Time for (compost) tea in the Northwest. BioCycle 41: 74-77 The potential of compost tea to provide nutrients and combat infection in plants and crops is discussed. 2001. C. BioCycle 42 24-25.000 cubic yards per year. Teas versus leachate.P.
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. Washington. A. L. Potential health hazards that may be associated with the use of compost tea on golf courses are addressed in a question and answer format. However. ------------------------------------------------------------------------------------------------------------------------------Naylor. Studies are being conducted to see if the compost increases the survival rate of transplanted native plants grown on site to restore the habitat. Using compost tea on golf courses. --------------------------------------------------------------------------------------------------------------------------------Touart. ----------------------------------------------------------------------------------------------------------------------------Salter. 2000. small trials were started. Compost tea is derived from finished compost and implies a more deliberate extraction process. of Eugene. and Soilsoup Inc. especially if made from improperly composted materials. whereas compost leachate formation is passive and secondary to the composting process. 2001. it is unlikely that incidental contact with areas treated with compost tea would result in illness. Compost tea contains microorganisms that have been active in the composting process but can include human and animal pathogens. BioCycle 42: 24 The differences between compost tea and compost leachate are addressed in a question and answer format. A compost tea has also been made and is being used on the Presidio's golf course as top dressing. The next stage was to expand the production of quality compost from 100 to 2. Oregon. The effectiveness of compost tea as demonstrated by experimentation is considered.organizations. Schoolchildren from San Francisco come every week to help with and learn about composting. of Seattle.

OR. In mid-June. The block with high levels of mildew was sprayed with fungicide. This is work being done with the Sustainable Studies Institute. During the week of August 5. In the weekly block. The results from the trials were that grapes in the tea-treated areas were ready for harvest weeks before conventional grapes were ready to be picked. maintaining protection was critical. at Wren tea was diluted 1:1 and at the McMinnville vineyard. During the summer. Initially the teas made were barely acceptable in terms of bacterial biomass. In the Wren vineyard. mildew was found on some grapes during the week of August 5. but the problems with extraction and compost quality have proven too difficult. except in the untreated control areas. OR. the second in Wren. OR. In this experiment. worm compost was mixed with some strongly fungal mushroom compost. but there are times when practicality overcomes any other consideration. indicating that mildew was in epidemic proportions and all growers should be aware that it was perfect conditions for mildew outbreaks to occur. reported mildew. The anaerobic tea tested the weeks of August 12 and 19 did not result in any improvement in organism coverage on leaf surfaces. and increased to no dilution in both blocks. No mildew was observed in the McMinnville vineyard. and the third in Monroe. which ended the mildew infestation. mildew was found in the block that had been last sprayed the week of July 20. but the mushroom compost was shown to contain many inhibitory compounds which killed the other organisms in the tea. OR. in the block sprayed every other week. a mildew alert was released by the OSU Extension Service. and the block went back to normal tea applications. We intended to find strongly fungal materials and apply a strongly fungal tea. the tea applications returned to weekly and bi-weekly. None of the vineyards.
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. and thus became the untreated control. at either application rate. and had only received tea sprays every two weeks. Therefore.Experimental Results
SARE grant (2001). 2001. because initially. The last week of July. The compost being used was changed. since the tractor had been fixed. Once mildew was observed. At the Monroe vineyard. Small levels of mildew were found in the weekly block. and this application will be a part of the next year’s study. The experimental design was application of a good compost tea to five rows of the vineyards every two weeks. These are the joys of having budgets. Eugene. no dilution was used. and no tea was applied for three weeks. the tractor at the Monroe vineyard broke down. tea sprays were initiated and no further mildew was observed. Clearly. compared with the control which is the rest of the vineyard using the grower’s normal practices. Three 12 gallon Micro-Brewers were donated to the Sustainable Studies Institute for use in this study. The next compost used was a combination of strongly fungal worm compost and strongly fungal thermal compost. Once the danger of infection was over. One is in McMinnville. we are working with three different vineyard cooperators in the Willamette Valley. but as it became difficult to afford the thermal compost. which had not been sprayed since the week of July 20. each vineyard diluted the tea to the correct amount to cover the rows within their vineyard. anaerobic teas were made and applied once. because of growers’ practices. strictly fungal worm compost was used. Because we were limited in the amount of tea being made per batch. but two rows were not sprayed. No further mildew spread was observed. tea application ended the mildew outbreak. Application starting times in the spring varied in each vineyard. and were almost completely lacking in fungal component. This wasn’t the experimental design. tea application was increased to once a week. application to a different set of five rows every week. This reduction in ripening time is significant with respect to being able to initiate wine-making operations in the late summer. this meant the tea was diluted 1:5.

because of the late frost. In general. mostly bacteria. powdery mildew outbreaks were largely controlled. Fungicide applications began on 23 July. Compost tea and disease suppression Compost teas applied to Wren. and that the level of bacteria and fungi on the leaf surfaces is critical. and not to the application of compost tea. On 8 August. and active fungal biomass. Fungal biomass declined in some areas sprayed with compost tea. Changes in soil microorganisms between 2001 and 2002 were also documented. in areas sprayed weekly with compost tea. On 23 July. The first application of fungicide was made on July 27. in both the weekly and biweekly spray plots. PM was found on 19 July in the plot sprayed biweekly. A sample taken on 11 Sept. Few of the teas contained the 10 micrograms of fungal biomass found to be sufficient for disease suppression in 2001. In the vineyards used for this study. At Broadly vineyard. as it was in 2001. on 23 July. At the R & R vineyard. As in 2001. showed only 3% leaf surface coverage.These results clearly show the importance of dose-rates. a project manager will be responsible for all treatment applications and sample collection. active bacterial biomass. 60% of the leaf surface was covered with organisms. These measures halted the progress of the PM
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. percent coverage of the leaf surface by bacteria increased significantly relative to pre-spray samples and unsprayed controls. and therefore leaf surface coverage by microorganisms. particularly fungi. but was more prevalent in the biweekly spray plots. total fungal biomass. The fungicide was applied three more times in August. Next year. followed by two applications of compost tea at twice the normal rate. the vineyard manager noted that most of the fruit on the vines sprayed biweekly had been lost to PM. Leaf samples from R & R were not replicated due to miscommunications. PM was first noted on 20 May in the CONVENTIONALLY-treated area. On 16 July. to control the powdery mildew fungus. Miscommunications and inconsistencies between protocols and application rates in the different vineyards have made it clear that all sites must be under the control and the responsibility of one grant-paid person. SARE grant (2002) Powdery mildew was a serious disease problem at vineyards in the Willamette Valley of Oregon in 2002. the usual cultural practice of thinning vines had not been performed in the rows being sprayed with compost tea as of 31 July. In 2002. Organism biomass in the teas. the disease was found in both weekly and biweekly spray plots. Weekly compost tea applications reduced the number of applications to one to as many as three applications of chemical fungicide needed to control powdery mildew over the summer growing season. Due to the late frost this spring at the Wren vineyard. but these rows were not scheduled to be harvested. Broadly Vineyards and Reeds and Reynolds vineyard contained similar levels of total bacterial biomass. probably due to the presence of a dessicant sprayed on 10 Sept. or their severity reduced. This area of the vineyard received seven applications of fungicide. however. In a sample taken on 11 July. Thus. so most likely these changes are in fact seasonally related and not the result of compost tea application. it is clear that SOIL organism biomass changes were due to other environmental factors or management practices. On 5 September. and very rarely reached the 2 – 5% level found to give effective disease control in 2001. the disease was first found at Wren on 25 July. disease pressure was higher from powdery mildew (PM) than from botrytis. Foliar sprays did not significantly improve soil biology in this two year study. bacterial activity was higher in 2002. not the manager of each vineyard. PM was present in both treatment areas. Organism biomass in soils from conventionally-treated areas followed similar patterns. Percent coverage by fungi did not increase relative to pre-spray samples or unsprayed controls. When teas were applied to leaves. was not sufficient to prevent infection. This area received only one application of fungicide. PM was found in both plots sprayed with compost tea. and reduced investment by the vineyard manager.

even if the crops in the treated areas are jeopardized. The maximum bacterial. protozoan and nematode numbers occurred between 18 and 24 hours in the brewing cycle. each well examined directly using DIC to allow identification to genus. Holland. Sylvia et al. no teas were brewed due to difficulty obtaining compost that was suitable for the project. Using a prototype of the Microb-Brewer. 1994. It was immediately after this two week period that mildew outbreaks occurred in the vineyard. so a tea maker manufactured by Compara International. Protozoan numbers and species diversity were determined from MPN plates. 1985. one single project manager should be solely responsible for making compost and applying teas. the Soil Microbial Biomass Service at Oregon State University used compost provided by Ron Stewart of Columbia Gorge Organic Fruit Company. The classic study on the effects of improved soil diversity on plant production was performed by Ingham et al. three teas were applied at 38 gal/ acre to both tea plots because the sprayer setting had been changed while the unit was being serviced.. For two weeks in August. Irregularities due to mechanical problems and weather will always occur. but changes in management practices and treatments need to be controlled. In further studies. 1995.
During 2002. two teas were sprayed at 50 gal/acre in a successful attempt to halt the progress of a mildew outbreak. At Broadly.
Microb-Brewer Experiment #1. was located and used.the EPM tea maker at Sunbow Farm was leaking and could not be used. miscommunications occurred regarding sampling and consistency in applying compost tea treatments between vineyards. Diversity was assessed by morphological characteristics during direct microscopic examination and colony morphology on spread plates. fungal. In the brewer.
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. Nematodes were identified following concentration of the tea using a 5 um mesh size screen sieve. and identification to genus by direct examination using DIC. Microorganism biomass was assessed using direct methods. 1998. Coleman and Crossley. Both fungal and bacterial biomass were determined using fluorescent stains and UV epi-fluorescent microscopy or Differential Interference Microscopy (DIC). and collecting samples.. the quantity of beneficial organisms was improved and pathogens were not found. We have learned that the growers who are involved in the project must be willing to follow the experimental protocol. At the R & R vineyard. Communication was not maintained as well as expected. but the entire literature is reviewed in Killham. Application rates of compost tea varied occasionally from the standard of 25 gal/acre.

tomato seedlings
were grown in the greenhouse and planted in three fields in different areas of the upper Willamette Valley near Cottage Grove. Four different treatments were applied to plots in these three fields: (1) Conventional practices. The tea produced contained very few organisms of any kind. as well as the leaves. et al. several conclusions can be drawn from these results: Using Good Compost is critical – Compost stored in a barrel and watered several days before use was tested.Grape Foliar Experiments. as
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. it was found to have become anaerobic based on active bacteria. less than 1/4 inch in diameter Barely noticeable mycelial strands on surface. 1/2 inch in diameter Barely noticeable growth of mold. foliar tea applied every 10 days to 2 weeks. 1/2 inch in diameter One spot of mold. (3) Tomato planting tray soil soaked with tea before planting. Following spraying of each tea.
% of grape leaf covered by tea bacteria 0% (No tea. 1991). it is probably most useful to test leaf organism coverage (Leaf Organism Assay). and leaf surfaces were found to be not adequately covered – only 22 to 30% coverage. and tea was made from that compost using an early-design Microb-Brewer. The following data demonstrates that this protective biofilm inoculated onto a detached leaf surface by compost tea suppresses disease. fungi. total bacteria and protozoan analysis. Tea was made using the standard Bacterial Tea recipe and using buffalo compost with a strong fungal component. You may also want to investigate where along the tea making process tea quality is being reduced. an immediate re-spray of better compost tea is indicated.H. However.. Is the compost good compost? Does it contain the organisms needed for the application you are using it for? This is bacteria and fungi for foliar sprays. leaf coverage was monitored in the Territorial Seed Company tomato trials. The compost was tested two different times. no visible colony growth No Botrytis. Leaf surfaces were tested for coverage by the beneficial organisms. This is not adequate to exclude or inhibit disease-causing organisms from the leaf surfaces. When designing a testing scheme. less than 1/4 inch in diameter Barely noticeable growth of mold. Table 12. Relation between leaf coverage and prevention of Botrytis on wine grapes. OR. because the compost contained few organisms of any kind. so you know whether you achieved adequate coverage or not. Results from this work will be published in a scientific journal. If coverage was not adequate. and if disease-organism spores or cells are dispersing. There are beneficial bacteria and fungi on leaf surfaces that protect plants from disease as well as produce and retain nutrients (Andrews. Summer 2000 – During the summer of 2000. protozoa and nematodes for soil applications. (2) A single foliar/soil drench immediately after planting. that the tea contains the organisms needed. Results are returned from the lab within 24 hours. This demonstrates the importance of knowing that the compost contains the organisms needed. No visible signs of disease on leaf
Territorial Seed Experiment. water only) 10% tea 20% tea 30% tea 60% tea 90% tea 90% tea % of grape leaf challenged by Botrytis cinerea 70% 70% 70% 70% 70% 70% 0% Visual observation of grey mould growth on leaf surface Visible growth of mold occupying 1/3 of leaf surface One spot of mold. bacteria. Seasonal Variation in Organism Activity on Leaves – Through the summer. and Foliar/soil drench at planting. J.

24 hours and 48 hours after spraying. M. fungi. mature. OR. but also with good moisture levels (45%).The kind of compost used to make tea made a difference in level of disease-organism incidence on both leaves and tubers. More studies of organism survival on leaf surfaces need to be performed to indicate how often tea sprays need to be performed in different weather conditions. the organisms did not remain active on the leaf surfaces for more than 25 hours. The best reduction in foliar disease occurred when still-warm (100° F). Addition of yucca (a product called Saponyn from Helena Chemical Company which does not contain preservatives) to tea in other trials appeared to improve organism survival on the leaf surface. rainy weather. dry weather. protozoa and nematodes. compost tea was the only application made to the potato plants during the summer besides routine and standard irrigation water. This compost contained highly active bacterial populations. cool periods. but to three plots within the randomized design. leaf surfaces were monitored immediately. while for a soil application. fully mature compost that was at ambient temperature. was effective at controlling tuber disease-organisms levels (reduced to less than 3% of tubers with disease-organisms infecting their surfaces.documented by analysis of the compost. A number of treatments were within the experimental design. to see if combinations of this kind would improve growth on leaves during wet. Oregon State University. Oregon State University) was applied to all plots during the late summer. was applied every 10 to 14 days to three plots. stickers may need to be added to the tank to improve retention on leaves. The results of these trials will be published in scientific journals. Wilt inoculum (Dr. Fungal biomass. Controls using standard conventional practices were maintained. however. In cool. During warm. The tea containing all the organisms would be more generally useful.
Potato Trials at Oregon State University
Potato field plots were established a number of years ago at the Oregon State University Lewis Brown Farm just outside Corvallis.
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. Results indicated that through the summer. sprays may only need to be done once every two to three weeks.) This mature compost tea had fewer active bacteria than the immature tea. for a foliar application. based on no significant difference from the control tubers with 60% of tuber surfaces covered with disease-organism as assessed by visual surface inspection and confirmed by plating on PDA. It is important to recognize that the set of organisms in the tea can vary. immature compost might be the best choice. more fungal dominated compost with higher numbers of protozoa and nematodes would be the better choice. Tea from Different Composts versus % Disease Suppression . the organisms in the tea (good biomass of bacteria. but not quite as well as the immature compost tea. A. which transferred to the tea and grew rapidly during the 20-hour tea brewing cycle. and that this may influence the application for which the tea is best suited. These plots were maintained by Dr. dry weather. In warm. survival of the organisms on the leaf surfaces varied with weather conditions. In cool. and using the standard Bacterial Tea recipe. the tea made from older. Department of Agronomy. protozoa and nematode numbers were low in this tea. as well as increase their ability to remain on the leaf surface through rainy conditions. It may be a good idea to assess combinations of dormant oils and teas. but also contained good numbers of fungal biomass. moisture-maintained (54% moisture) compost was used. This tea reduced the presence of foliar infection as well. rainy weather. Thus. Mosely. However. However. the organisms on the tomato leaves remained very active and increased in number. protozoa and nematodes present in the tea produced by the Microb-Brewer) and the leaf surfaces (Leaf Organism Assay). Compost tea. This tea was not effective at controlling tuber infection. but the tea with high bacterial activity was the most useful at reducing the presence of foliar disease-organisms on the leaf surfaces. made with a Microb-Brewer. Powelson. several conclusions can be drawn from the trials.

often pathogenic properties Beneficial Organisms—Non-pathogenic life. most of which are strictly aerobic bacteria. and highly condensed. spore-forming bacteria. These organisms generally switch from aerobic to anaerobic metabolism at low oxygen concentrations. Aerobactor—A specific genus of bacteria. Mycorrhizal Fungi . Butyric Acid—A volatile organic acid produced through the incomplete anaerobic oxidation of organic matter. typically identified as sour milk smell. such as making beer. aerobic. any container in which metabolic processes are being performed. called the Hartig net. Fermentation—A specific group decomposition process that typically involves the production of carbon dioxide. includes both fulvic and humic fractions. occurring in many forms. these can be used by bacteria. high molecular weight.VAM are a set of mycorrhizal fungi that form arbuscules and vesicles within the roots of plants. long-turnover time organic compounds in soil. Aerobe—Any organism requiring atmospheric concentrations of molecular oxygen as the final acceptor in metabolism. but use very different metabolic pathways depending on oxygen concentration. Turnover time in soil may be 300 to 3000 years. molds.000 to 600. Disease Suppression—The ability to inhibit. Strict anaerobes typically are killed by even the slightest oxygen concentrations. any rod-shaped. preventing disease-causing organisms from detecting the root. often occurring in chainlike formations. smuts. composed of extremely recalcitrant. or which organisms cycle a particular nutrient within an ecological community. while ectomycorrhizal fungi form a net. such as temperature. production of metabolic waste products and carbon dioxide. proteins. within the first one-to-
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. typically 2000 to 6000 dalton length chains. Humics—The mixture of all recalcitrant. Very resistant to decomposition. Anaerobe – Any organism requiring reduced oxygen concentrations. Fulvic Acid—A particular fraction of complex humus material composed of medium molecular weight long-chain organic compounds. ranging in form from a single cell to a body mass of branched filamentous hyphae that often produce specialized fruiting bodies and including the yeasts. Metabolites—Organic compounds produced by metabolic processes. Bacillus—A specific genus of bacteria. Bacteria—Unicellular microorganisms. hormones released by plants into the environment. rod-shaped. or consume disease-causing organisms preventing them from causing disease. carbohydrates. very long-chain organic compounds typically 6. Fungi—Plants of the division Thallophyta. humidity.Simple sugars. Fermentor—A vessel used for fermentation processes. typically Gram-positive. compete with. wine. Wine or beer fermentation. Humic Acids—A particular fraction of complex humus. generally with biomass production by the organism doing the decomposition. inorganic chemicals. Broadly applied. often improving the growth of a desired organism in a moreor-less mutualistic association where both organisms benefit from the presence of the other. or elevated carbon dioxide concentrations in order to be able to perform metabolic processes. Exudates. Used generically. while facultative anaerobes can function in both aerobic and anaerobic conditions. chain-forming bacterium. Both aerobic and anaerobic processes can be included as fermentative process. Facultative Anaerobe—Organisms that can perform metabolism using either oxygen or inorganic molecules as the final electron acceptor in metabolism. although usually this term refers to anaerobic fermentation where alcohol is produced.000 daltons in lengths and highly structured in a three-dimensional manner. Usually meaning physical or chemical factors. existing either as free-living organisms or as parasites. for example.Glossary
Abiotic—Not biotic. lacking chlorophyll. not related to life or specific life conditions. Foodweb—The set of organism relationships. Of the recalcitrant humic materials. and mushrooms. typically for the express purpose of encouraging the growth of bacteria and fungi which form a biological shield around the plant. Decomposition—The process of conversion of organic material from one form to another. with a broad range of biochemical. often based on who-eats-who. Turnover times may be 100 to 300 years in soil.

or leachable. sands. When growing conifers. Phenols—A benzene carbon ring structure with hydroxyl groups at various positions attached to the carbons in the ring. Valeric Acid—A volatile organic acid produced through the incomplete anaerobic oxidation of organic matter. Nutrient Cycling—A biogeochemical cycle. as opposed to a decomposer. the process of conversion of organic and inorganic material from one form to another. a primary producer that uses sunlight for energy. Protozoa—A group of single-celled animals whose major prey group is bacteria. Because bacteria contain much more N per unit C. Vortex Nozzle—Used in the Microb-Brewer. the amoebae. nitrite. Retention requires nutrients to be physically immobilized by inclusion in organic matter (in organisms or organism waste-products such as bacteria. clay parent material) are bound together through the actions of microorganisms. generally with the production of biomass by the organism doing the cycling. Soluble—Capable of being dissolved in water. Taxonomic revision of this group of species is underway. ectomycorrhizal fungal experts should be consulted. typically identified as a vomit smell. Strict anaerobes will be destroyed when they come in contact with di-oxygen. for example. are the mineral forms. and by the larger faunal organisms in soil. Amoebae can be separated into naked amoebae. a system regarded as analogous to a living body. The more aggregated the soil. determines in part how water. and the most mobile. silt. as their membrane structure is broken down by these compounds. silts or organic matter. The three major groups of protozoa that occur in soil are the flagellates. sulfite. Pseudomonas—A genus of bacteria. some species in this genus are plant-pathogens while some are extremely beneficial to the growth of some plants. which consumes dead plant material. Nutrient Retention—The opposite of leaching. the Vortex Nozzle creates a high velocity atomization of tea and air within the chamber of the nozzle. extraction or loss of nutrients. Host ranges of row crops for VAM are quite broad. fungal-feeding. typically resistant to enzyme attack and therefore considered relatively resistant to decomposition. The least mobile nutrients will nearly always be the organic forms. and testate amoebae. and carbon dioxide.) as the final electron acceptor in metabolism. plants or plant detritus) or by chemically binding on the surface of clay. nitrate. Prey–– An organism that is eaten by a predator. N is released as ammonium. or ozone. There are four major functional groups in soil including bacterial-feeding. Many phenols have antibiotic or toxic capabilities. Nematodes—Any of various worms of the phylum Nematoda having unsegmented threadlike bodies.two cell layers of feeders roots and send rhizomorphs along the root surface. predatory (eat other nematodes) and root-feeding. a plant available form of N. fungi. in solution. and the space between these particles formed through the bonding action. in both small and larger ped structures. Predator ––An organism that consumes other living organisms.
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. Organism—A plant or animal. sulfate. Soil Aggregation—Soil particles (sand. production of metabolic waste products which serve as the next step in the nutrient cycle. Strict Anaerobe—Organisms that perform metabolism using oxidized forms of nutrients (carbon dioxide. the important factor to understand in choosing species of VAM is climate. roots and nutrients will be held by that soil. and the ciliates. etc.

ofrf.pdf A 12-page PDF download.woodsend.” which describes looked at the effectiveness on compost teas to suppress diseases on strawberries.pdf The full OFRF report reviewed above.html I highly recommend this manual to anybody who plans to make and use compost teas.birc. a Biodynamic journal reprint http://www.50 total through: Bio-Integral Resource Center (BIRC) PO Box 7414 Berkeley.org/publications/news/ib9.org/compost_tea. beneficial organisms.pdf An 8-page PDF download. microbial food resources for different micro-organism groups. application methods.org Investigations into Liquid Compost Extracts (“Teas”) for the Control of Plant Pathogenic Fungi By William F.1of11. Brinton and Andreas Trankner. 2000..woodsend. compost tea production methods. Inc. factors affecting compost tea quality. so be patient waiting for it to download. Written by Dr. and broccoli in British Columbia. Ingham. Compost Practices for Control of Grape Powdery Mildew (Uncinula necator) By Andreas Trankner and William F. Included among the items in the compost teas issue is “Benefits of Compost Tea: A Review of the Research Literature.ofrf. a 51-page PDF download. a BioCycle conference paper http://www. matching compost teas to plants and soils.896K PDF file. 23. By Elaine R. and “Effectiveness of Compost Tea Extracts as Diseases Suppressants in Fresh Market Crops. which describes and illustrates a homemade on-farm compost tea brewer. featuring the work of Dr.org http://www. The IPM Practitioner. p. 1–8. Elaine Ingham. Organic Teas from Composts and Manures Richard Merrill. William Brinton of Woods End Research Laboratory in Maine. The September 2001 issue of The IPM Practitioner—the monthly journal from Bio-Integral Resource Center—featured compost teas. http://www. Other items include: “Apparatus and Experimental Protocol for Organic Compost Teas”.org/will2. OR. Brinton.org/publications/Grant%20reports/97Fall. with 88 literature references in the bibliography. Organic Farming Research Foundation Information Bulletin No. An 8-page reprint is available for $7. William Brinton of Woods End Research Laboratory in Maine.pdf The full OFRF report reviewed above.
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. compost tea recipes. No. Vol. leeks. 60 pages.Merrill97-40. This is a 1. Soil Foodweb.Welke99-31. OFRF Grant Report 97–40 http://www. Effectiveness of Compost Extracts as Disease Suppressants in Fresh Market Crops in British Columbia Sylvia Welke. bacterial vs.pdf The Winter 2001 issue contains a special report on OFRF-funded compost tea research.Recent Literature and Resources
by Steve Diver (reprinted by permission)
Compost Tea Brewing Manual. Winter 2001 http://www.org/publications/Grant%20reports/99Spr. but the full report—see below—contains 88 references in total. it provides a practical summary of compost teas underpinned with a scientific understanding of applied microbiology. pages 820.” Compost Tea for Organic Farming and Gardening.soilfoodweb. By William Quarles.1of5a.ofrf. Corvallis.com/multimedia/compostteamanual. “Selected References for Organic Tea Extract Studies. OFRF Grant Report 99–31 http://www.IB9. a 10-page PDF download. 9. featuring the work of Dr. fungal dominated compost teas. CA 94707 510-524-2567 510-524-1758 Fax birc@igc. lettuce. 9 (September).” It lists 53 citations. including: how to use compost teas.IB9. and experimental results.

Historically. phenols. The end product of anaerobic decomposition may also contain alcohol. When Karl Rubenberger brought his hi-tech compost tea brewing machine to Dr. De Agriculturia). aerobic environments. But brewing methods remained fairly low-tech – dump some stuff in water and let it sit with only a few stirs . Different plants require different sets of organisms in the soil. initially a big vat aerated by stirring the liquid occasionally. but brews often go through an anaerobic phase if growers are not careful. Once anaerobic. you can maintain its growth and maximize productivity by building the soil and improving life in that soil. nematodes and microarthropods to build soil structure. Old-growth forests are at the other end of the scale. Making manure tea is a common practice in Biodynamics. but the fungi have even greater biomass than the bacteria in perennial systems. When compost (or compost tea) is made in anaerobic conditions.
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. and can be fraught with problems if the products of anaerobic metabolism are not taken care of before use on plants. brassicas. nematodes. fight pathogens and pests. Many of the BD preps he described are specifically for use in stirred teas. Dr. manure tea and plant teas – or tinctures – in various ways. This ensures that the finished product is rich in nutrients and beneficial organisms. Weeds. Elaine Ingham at Oregon State University in 1993. making tea can take weeks. Steiner’s descriptions of tea making suggest using additives in low concentrations. Biodynamic growers have been using the “low tech” approach since Steiner recommended its use. the tea needs to be brewed until the liquid returns to the aerobic phase. just more bacteria than fungi). Most flowers and vegetables grow best in soils that have balanced bacterial and fungal biomass. Robert Cantesano of CCOF (California Committee on Organic Farming) began the movement toward more hi-tech methods of brewing by adding air pumps and dripping the tea through the compost. This research is yielding some fascinating information.until the early 1990’s when Karl Rubenberger started a revolution in the tea-making industry. Ingham’s career has been devoted to studying the biology in soil. has changed through the years. The most productive soils in the world are those with the most organic matter mixed through the surface soil horizons. dominated by fungal biomass. even earlier than that. The recipe and machinery used to produce tea. nutrients are lost to the atmosphere (which is why anaerobic compost stinks). Thus. Compost and compost tea need to be produced in oxygen-rich. however. protozoa. and early successional grass species grow best in soils dominated by bacterial biomass (there are fungi in bacterialdominated soil. Select for the plant you want by making certain the organisms in the soil support the needs of that plant. There may actually be more bacteria in a fungal-dominated soil than in earlier stage of succession. microarthropods. and improve soil structure. Compost and compost tea can be used to improve the soil and foliar life required to protect plants from the diseases that abound in pesticide and fertilizer degraded ecosystems. This wealth of organic matter is used by beneficial bacteria. compost and compost tea. fungi. organic acids and proteins that are toxic to plant tissues. Ingham wanted to know why making tea in this way would be useful. Dr. most likely so that the tea does not go anaerobic. protozoa. While an aerobic–to–anaerobic-and–back–again tea can have quite useful effects. or brew when temperatures are too warm. And the collaboration between Rubenberger and Ingham began. and most likely. production takes too long for most growers. Once you have the right balance for the plant you want. growers made compost tea. fungi.The History of Compost Tea
Compost tea has been with us in some form since the Roman Empire (Cato. earthworms and other soil critters that work together to feed plants. Her professional career has been focused on learning about the “soil food web” which is the complex web of bacteria.

Other people started to build good compost tea machines by 1998. put together and tested in a complete and thorough fashion. The bacteria. consistent. The original machine tested at OSU produced a water vortex to pull the organisms out of the compost. maintaining aeration and excellent organism growth in the tea. These machines pull the biology. When bio-film developed. Compost tea includes the whole set of organisms extracted from good compost. After this change. it could be seen and removed by cleaning. saying that the lab did not know what they were doing. teas began to arrive at Soil Foodweb Inc. Many different food resources were tested. which improves growth and boosts yields. excellent fungal tea machine was made. The nutrient mixes developed for these machines enhance the beneficial organisms in the compost. and the problem was solved. it was claimed that SFI testing was questionable. that SFI was just interested in making money because of the insistence that tea machines be tested. a 500 gallon machine. they are protected from disease-causing bacteria and fungi. smelly. In 1999. of course. and that the SFI methods were not reliable. the machine was re-plumbed with solid PVC pipe material to replace the plastic tubing. Cleaning was made easier by easy-release connections. and the soluble nutrients. and a reliable. In 1996. with reduced fungal biomass. so SFI kept trying to determine the reason for the lack of acceptable sets of organisms in the teas. especially fungi which cannot tolerate anaerobic conditions and cannot compete with most anaerobic bacterial species. anaerobic bio-films developed in the pipes that had replaced the plastic tubing. and the reason for the low activity and biomass could not be determined. The 5 gallon “Keep-It-Simple” machine makes excellent tea in 12 hours. as the reputation of the Microb-Brewer had been harmed by the problems with the pipes. Bruce Elliott. If the tea contains no organisms. and the main benefit of tea is just the nutrients extracted. from the composts used. with bio-film formation and anaerobic conditions developing in the machine. There is no need to brew for 24 hours to just extract nutrients from compost. While these machines use pumps through which the tea passes. a great deal of testing has been done to make certain the pumps are not harmful to the organisms. and again. Leon Hussey was the next to develop a tea machine that works well. the Compara Extractor is used through most of Europe for commercial compost tea production. the Dutch company. each one tested to make certain it produces tea with excellent levels of organisms. But compost tea is. SFI was blamed. protozoa and nematodes are the reasons compost tea is beneficial to plant growth. The new system that was developed had serious drawbacks. then it is easier to buy liquid organic materials.Compost tea applied to the foliage of plants increases the biological activity on the leaf surface layer. A simple and easy-to-clean machine. The manufacturer of the Microb-Brewer decided to no longer make the Microb-Brewer. When leaf surfaces are coated with a layer of beneficial bacteria and fungi. fungi. and finally. The claim was made that fungi did not grow in tea. The machine did not result in tea with decent fungal biomass. it was determined that thick. The manufacturer blamed Soil Foodweb Inc for the problem. The solution was simple: replace the solid pipes with plastic tubing. more than the soluble nutrients. it could be seen easily and cleaned. which increases the length of time the plant stomates are open. built a tea brewer based on tube diffuser designs. With time. But when the manufacturer decided the machine needed to look more professional. and specifically the beneficial organisms that grow in aerobic conditions. of EPM. Karl Rubenberger turned over production of his tea machine to a manufacturer. This increases the opportunity for nutrient uptake. EPM has made 100 and 22 gallon machines. But the teas did not perform in the field the way they were expected to perform. 24-hour compost tea machines began. The anaerobic products harmed the organisms. and commercial production of highly aerobic. so when biofilm developed. Compara. and had no pipes on the bottom of the machine. These pipes could not be easily removed or cleaned. Eventually. It is
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and if the compost used contains the needed life. New South Wales. Can “brought-back” tea be beneficial? Yes. and then grows the organisms while they are on the way to your field. These machines have been tested. Anaerobic conditions in the tea will result in the loss of the beneficial fungi. flagellates. if the bacteria now growing in the tea are quite beneficial species.nearly impossible to overwhelm this tea machine with too much food resource. based on swirling air through the water. New South Wales. in more than one run (means and standard deviations have to be given. followed then by loss of flagellates and amoebae. with adequate extraction of the organisms and foods from the compost. Any compost tea machine must be able to substantiate that all of the organisms in the compost are extracted into the tea by that machine. through which the air is blown. These machines use air bubblers to produce the tea. and be growing. Excellent results are typically seen using this large-scale air bubbler type brewer. with no toxic anaerobic materials produced. Australia has also developed a good tea brewer .Charlie Clarke machines were next on the market. coli will almost never grow in the tea. which are undergoing testing at this time. Dennis Hronek designed a compost tea extraction unit. human pathogens cannot be prevented from growing in the tea. and to have adequate levels of active bacterial biomass. If an anaerobic tea is held for longer than 24 hours. With loss of aerobic organisms resulting from anaerobic conditions. those organisms will be extracted into the tea by compost tea machines. Bacterial tea cannot be expected to give the benefits that a true compost tea gives. E. Control of many foliar fungal pathogens will be difficult. Without this documentation of consistent beneficial organism growth in the tea. amoebae. machines calling themselves compost tea makers should be viewed with extreme skepticism. Aeration is maintained by a variable speed blower that can be tied to the actual concentration of oxygen in the tea. If the machine is not capable of extracting the organisms. results in excellent organism production and growth. however. These machines use tubes with outer liners of plastic with fine holes in it. The extractor units are amazing in their ability to remove the organisms from the compost without requiring a growth period. total bacterial biomass. coli above acceptable levels. The next tea brewer produced was by the Compost Tea Company in New Zealand. and several other growers in Australia have built tea makers. then it is not a compost tea machine. to remain aerobic. active fungal biomass. total fungal biomass. blowing air into the tea. In order to do this. If the compost has good organism numbers and diversity. The movement of air through the water column also mixes the water through the compost. because the beneficial fungi that protect the plants from those pathogens will have been lost.
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. Compost Solutions in Coffs Harbour. then the detrimental conditions can be alleviated. and as a result. and should not be called such. and buyers must be aware of the differences. highly consistent. The James Sottilo . which extracts the organisms from the compost very efficiently. The likelihood that the beneficial fungi will still be present. and Tryton. Nutri-Tech. Only a combination of high foods and really poor compost will result in the tea having E. The lessons learned in these first few years of aerobic. and oxygen allowed to diffuse back into the water over the course of several days to weeks. 24-hour tea brews is that the machines have to be tested and proven to stay aerobic in order to produce tea containing aerobic organisms in high numbers and high diversity. in Lismore. is just about nil. which causes mixing through the compost. The Simplici-tea company which makes the KIS brewers. But it can take weeks to out-compete the human pathogens and decompose toxins produced during the anaerobic period. or multiple runs with data from all runs shown). High ciliate numbers are indicative of the use of a poor compost. machines have to be documented. has added a 30 gallon machine. which has developed an industrial strength brewer for that country. and moving the compost bag continuously through the first few hours of the brewing cycle. ciliates and beneficial nematodes.

fungi.g. and www. If the reports on the SFI website show that growers cannot obtain decent organism numbers using the directions the tea machine maker gives them. Soil Foodweb Inc will continue to do research investigating the growth of different kinds of bacteria.. answers for all growers.com (there’s an underline between compost and tea in the name).Once growers are certain that the machine they have is capable of extracting the organisms. and the grower should be able to achieve good results (e. and SFI is committed to investigate those issues. total bacteria and total fungi) the very first time they use a commercial tea brewer with its nutrient starter mix. SFI tests teas made by growers using commercial tea machines. Good brewing! Elaine R. We want to supply the best.intlctc.g.Vaclav Havel. Talk to other growers about tea machines. but one we’ll do our best to achieve. former President of the Czech Republic
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. then that machine should be considered too risky to buy. are: compost_tea@yahoogroups. active fungi. the highest flavor. or pests? All these issues have to be understood. protozoa and nematodes in soil. the equipment needed to apply tea. foods that can be used in making compost tea. It is not the belief that things will turn out well. no matter how things turn out. Ingham "Hope is not a feeling. and least expensive. compost and compost tea. good active bacteria. etc. no matter where they are in the world. Commercial machines should have data for their machines. A big order. then the additives need to be assessed. the tea stays aerobic). What are the conditions that allow different plant species to grow better than any other plant? How do you know that the conditions in your soil will give the best yields. but the conviction that what we are doing makes sense..org Over the next few years. and anyone offering a product without any solid data to back-up their claims will always let the grower down when the machine does not perform as promised." -. and will allow those organisms to survive (e. Good places to obtain information about making compost tea. with your help. the best color and longest storage times? Which beneficial organisms are the best at protecting the plant from disease. Hype is something all growers have to learn to detect.